This is a list of the where you can find the special zombies and know how rare they are. I took this information from the lua files.

---------------------------General Population----------------------------

Police Officers (Anywhere, 0.25% chances to find them)
Bikers (Anywhere, 0.05% chances to find them)
Fitness Instructors (Anywhere, 0.03% chances to find them)
Joggers (Anywhere, 0.02% chances to find them)
"Generic 06" (Anywhere, 9% chances to find them)
Naked Blue Veins (Anywhere, 0.001% chances to find them)

--------------------------Survivalists--------------------------
Police Officer Survivor (Anywhere, 0.03% chances to find them)
Hazmat Suit Survivor (Anywhere, 0.03% chances to find them)
Splatter Survivor (Anywhere, 0.03% chances to find them)
Ranger Survivor (Anywhere, 0.03% chances to find them)
Covid Survivor (Anywhere, 0.03% chances to find them)
L4D2 Surviror (Anywhere, 0.03% chances to find them)
CEDA Yellow Suit Worker (Anywhere, 0.03% chances to find them)
CEDA Green Suit Worker (Anywhere, 0.05% chances to find them)
CEDA Black Suit Worker (Anywhere, 0.01% chances to find them)
CEDA Blue Suit Worker (Anywhere, 0.01% chances to find them)
CEDA Red Suit Worker (Anywhere, 0.01% chances to find them)
Leon Kennedy (Apparently broken, 3% chances to find him)
Jill Valentine (Apparently broken, 3% chances to find her)

-------------------------- Various Male-Only/Female-Only outfits --------------------------

Mannequin (Anywhere, 0.5% chances to find her)
Male Student (Anywhere, 0.5% chances to find him)
Female Student (Anywhere, 0.5% chances to find her)
Evil Vegan (Anywhere, 0.05% chances to find him)
Country Hick (Anywhere, 0.04% chances to find him)
Neon Fitness Instructor (Anywhere, 0.08% chances to find her)
Will Smith (Anywhere, 0.05% chances to find him)
Playboy Bunny (Anywhere, 0.03% chances to find her)
Mad Max (Anywhere, 0.01% chances to find him)
Waldo (Anywhere, 0.01% chances to find him)
Free Hugs Girl (Anywhere, 0.0006% chances to find her)
Black Mamba (Anywhere, 0.0009% chances to find her)
Clementine (Anywhere, 0.0009% chances to find her)
Kate (Anywhere, 0.0009% chances to find her)
Uncle Sam (Anywhere, 0.0001% chances to find him)
Dukem Nukem (Anywhere, 0.001% chances to find him)
T h e y L i v e (Anywhere, 0.0001% chances to find t h e m)
TF2's Blue and Red Spies (Anywhere, 0.0001% chances to find him)
Michael Jackson's Thriller Dark Chocolate Edition (Anywhere, 0.0001% chances to find him)
"Fat Blart" (Anywhere, 0.0001% chances to find him)
"Fat Cheese" (Anywhere, 0.0001% chances to find him)

--------------------------The Clowns--------------------------

The Mimes (Anywhere, 0.04% chances to find them)
The Common Clowns (Anywhere, 0.04% chances to find them)
The Clown Party (Anywhere, 0.04% chances to find them)
The Barotrauma Clowns (Anywhere, 0.01% chances to find them)
The Obese Clowns (Anywhere, 0.01% chances to find them)
Wrinkles The Clown (Anywhere, 0.01% chances to find him)
Pennywise The Dancing Clown (Anywhere, 0.00001% chances to find IT)

-----------------------Football Players-----------------------

The Blue Star Football Players (Anywhere, 0.01% chances to find them)
The Football Patriots Players (Anywhere, 0.01% chances to find them)
The Football Green-Bay Packers Players (Anywhere, 0.01% chances to find them)
The Football Chiefs Players (Anywhere, 0.01% chances to find them)
The Football Red Skulls Players (Anywhere, 0.01% chances to find them)

--------------------------Left 4 Dead Survivors--------------------------

"Bill" (Anywhere, 0.0009% chances to find him)
Louis (Anywhere, 0.0009% chances to find him)
Francis (Anywhere, 0.0009% chances to find him)
Zoey (Anywhere, 0.0009% chances to find her)
Jimmy Gibbs Jr. (Anywhere, 0.0009% chances to find him)
Ellis (Anywhere, 0.0009% chances to find him)
"Coach" (Anywhere, 0.0009% chances to find him)
Nick (Anywhere, 0.0009% chances to find him)
Rochelle (Anywhere, 0.0009% chances to find her)

-------------------------Back 4 Blood Survivors--------------------------

Walker (Anywhere, 0.0009% chances to find him)
Evangelo (Anywhere, 0.0009% chances to find him)
Hoffman (Anywhere, 0.0009% chances to find him)
Holly (Anywhere, 0.0009% chances to find her)
"Mom" (Anywhere, 0.0009% chances to find her)

--------------------------Horror Zombies--------------------------

Ghostface (Anywhere, 0.00001% chances to find him)
Leatherface (Anywhere, 0.00001% chances to find him)
Freddy Krueger (Anywhere, 0.00001% chances to find him)
Michael Myers (Anywhere, 0.00001% chances to find him)
Jason Voorhees Part 2 and 3 (Anywhere, 0.00001% chances to find them)
Winslow (Anywhere, 0.00001% chances to find him)

--------------------------Room-Based Spawns--------------------------

Ice Cream Workers (Ice Cream Shops, 50% chances to find them)
Bathrobe Zombies (Bathrooms, 5% chances to find them)
Sports Fan (Recreation Places, 5% chances to find them)
Shaun (Bars, 1% chances to find him)
Homeless ("Drug Shacks", 15% chances to find them)
Bob Ross (Galleries, 3% chances to find him)
The Chicken Party (Jay's Chicken Restaurants, 3% chances to find them)
Bill Murray (Bowling Alleys, 0.1% chances to find him)
Ash Williams (BBQs, 0.1% chances to find him)
Hank Hill (Metal Shippings, 1% chance to find him)
Playboy Nurse (Small Medical Centers, 1% chances to find her)
Playboy Nurse (Big Medical Centers, 10% chances to find her)
Seahorse Worker (Cafe, 15% chances to find them)
G-Man (News Room, 3% chances to find I T )
Playboy Nurses (Strip Clubs,5% chances to find them)
Playboy Bunnies (Strip Clubs, 10% chances to find them)
Grindhouse Cherry (Strip Clubs, 1% chance to find her)
"Richard" (Strip Clubs, 1% chance to find him)
Neon Fitness Female Instructors (Workout Places, 20% chances to find them)
Killa (Factories, .001% chances to find him?)
Traveling Band (Picnics, 50% chances to find them)
Dianne Caldwell (Clothing Stores, 0.5% chances to find her)
Fitness Instructors (Workout Places, 25% chances to find them)
Joggers (Workout Places, 25% chances to find them)
Cheerleader from Louisville (School Laboratories, 3% chances to find her)
Cheerleader (Classroom, 3% chances to find her)
School Girl (Classroom, 5% chances to find her)
"Molotov" (Theaters, 1% chance to find him)
"Badass" (Theaters, 1% chance to find her)
"Roje" (Theaters, 1% chance to find him)
"Wally" (Theaters, 1% chance to find him)
Patrick Bateman (Theaters, 1% chance to find him)
"Jive" (Theaters, 1% chance to find him)
"Hunter" (Theaters, 1% chance to find him)
Venkman (Theaters, 1% chance to find him)
Stantz (Theaters, 1% chance to find him)
Spengler (Theaters, 1% chance to find him)
Zeddemore (Theaters, 1% chance to find him)
Abraham Lincoln (Theaters, 1% chance to find him)
The Joker (Theaters, 1% chance to find him)
Mall Security (Department Stores, 60% chances to find them)
Office Worker Skirt (Department Stores, 60% chances to find him)
Frank West (Department Stores, 1% chance to find him)
Dawn of The Dead guy (Department Stores, 1% chance to find him)
Flyboy (Department Stores, 1% chance to find him)
Brad Garrison (Department Stores, 1% chance to find him)
True Eye Cult Member (Department Stores, 1% chance to find him)
Jessie McCarney (Department Stores, 1% chance to find her)
Dr. Brown (Railroads, 1% chance to find him)
Marty McFly (Railroads, 1% chance to find him)
Miner 1 (Railroads, 10% chances to find them)
Miner 2 (Broken Railroads, 60% chances to find them)
Miner 3 (Train Car, 80% chances to find them)
------------------------------------------------------------------------------------
If you already noticed it, there is a few zombies left, many of them are very common (like fat ones) but I also left special zombies, however, for some reason it seems they are kinda broken. Finally, all the zombies have a chance to spawn in Valley Station Mall or Grand Ohio Mall, so if you can't find one of them, then check those places!