same problem here

Has anyone found a way to fix this?

me too

Oh wow. Seems like im not the only one to have that problem and nobody still answered. Nice.

Yeah, pretty sure this mod has been abandoned

Seems like it. Welp , i tried to solve all of this by editing files , but Civ5 sdk ModBuddy is not working and i gave up on that after trying to fix ModBuddy problem. Here is a forum link , maybe someone will be motivated enough. As for me - unsub and starting a new game.
https://forums.civfanatics.com/threads/tutorial-reskinning-vanilla-graphics.392773/
(You skip whole "creating a new model" thing and get to converting files and adding those to mod ,maybe that should do a trick)

I have this issue as well and have no idea how to fix it

Do y'all have RED installed? Units showing up as spearmen are typically because of art asset conflicts with mods. If you uninstall mods that change the models of units (RED makes things smaller and changes some units for country specific flair), it should work normally. This was an issue in my testing for a mod I did awhile back. Uninstalled RED and my mod worked just fine.

Disabled RED and Ethnic Units, even removed them from my mod folder but units still appear as spearmen :/

Found the problem. Earth 2014 civs conflicts with the mod.

Conflicts with Late-Game Unit Pack as well
Models are all spearmen

Disabled "Special Forces upgrade for Marine" mod worked for me.