here's my crash logs:
-Lua Stack Traces-
==================
Client
Lua Interface = NULL

Server
Lua Interface = NULL

MenuSystem
*Not in Lua call OR Lua has panicked*

-Console Buffer-
================
30(8.539878): env_cubemap used on world geometry without rebuilding map. . ignoring: metal/metalceiling005a
29(8.528219): env_cubemap used on world geometry without rebuilding map. . ignoring: metal/citadel_metalwall076a
28(8.505774): env_cubemap used on world geometry without rebuilding map. . ignoring: tile/milflr002
27(8.502424): env_cubemap used on world geometry without rebuilding map. . ignoring: de_piranesi/marblefloor14
26(8.500702): env_cubemap used on world geometry without rebuilding map. . ignoring: de_piranesi/marblefloor10
25(8.500500): env_cubemap used on world geometry without rebuilding map. . ignoring: tile/tilefloor012a
24(8.499701): env_cubemap used on world geometry without rebuilding map. . ignoring: metal/metalwall_combinecore03a
23(8.497844): env_cubemap used on world geometry without rebuilding map. . ignoring: wood/wooddoor045a
22(8.497652): env_cubemap used on world geometry without rebuilding map. . ignoring: de_piranesi/marblefloor06
21(8.497525): env_cubemap used on world geometry without rebuilding map. . ignoring: metal/citadel_tilefloor016a
20(8.496056): env_cubemap used on world geometry without rebuilding map. . ignoring: de_piranesi/marblefloor01
19(8.492777): env_cubemap used on world geometry without rebuilding map. . ignoring: de_piranesi/marblefloor08
18(7.936258): Extracting BSP to map.pack in order to mount BSP embedded content...
17(7.918071): PREP OK
16(7.791819): Extracting BSP to map.pack in order to mount BSP embedded content...
15(7.790906): m_face->glyph->bitmap.width is 0 for ch:32 Verdana
14(3.966104): Addons have changes - remounting
13(3.944013): m_face->glyph->bitmap.width is 0 for ch:32 DejaVu Sans
12(3.784602): SetLocale('en_US.UTF-8') failed. Using 'LC_CTYPE=en_US.UTF-8;LC_NUMERIC=C;LC_TIME=en_US.UTF-8;LC_COLLATE=en_US.UTF-8;LC_MONETARY=en_US.UTF-8;LC_MESSAGES=en_US.UTF-8;LC_PAPER=en_US.UTF-8;LC_NAME=en_US.UTF-8;LC_ADDRESS=en_US.UTF-8;LC_TELEPHONE=en_US.UTF-8;LC_MEASUREMENT=en_US.UTF-8;LC_IDENTIFICATION=en_US.UTF-8'.
You may have limited glyph support.
Please install 'en_US.UTF-8' locale.
11(3.753663): Advanced Joystick settings initialized
10(3.753657): JOY_AXIS_V: unmapped
9(3.753651): JOY_AXIS_U: mapped to Side (absolute)
8(3.753644): JOY_AXIS_R: mapped to Forward (absolute)
7(3.753638): JOY_AXIS_Z: unmapped
6(3.753631): JOY_AXIS_Y: mapped to Look (absolute)
5(3.753609): JOY_AXIS_X: mapped to Turn (absolute)
4(3.703352): Did not detect any valid joysticks.
3(3.250080): Parent cvar in server.dll not allowed (props_break_max_pieces)
2(3.248456): x86-64: gmod_mcore_test=1
1(2.043511): Attempting to load Chromium...

I found the solution. I had a similiar problem with getting it to run on a linux based server. The issue is the displacement power of the terrain mesh being at 4. basically the dirt has too many polygons. Unfortunately that's on the creator to decide wether to fix that or not, as lower the displacement power could break the terrain and make it look uglier. Not to mention it can be an extremely tedious task to do.

yea it works when i run it through proton