Adding new Creature won't work

So I was trying to create a mod which adds some better TEK stuff and a stronger and bigger Version of the Tek-Rex.
I put everything together, tested it in the engine itself and it worked fine.
Basic Idea of new Rex is this:
You get better quality Tek-Equip when you kill the new Tek Rex. Instead of adding Spawns all over the maps, I decided to go with craftable Spawner, just like Wildcard did with MEK.

So I copy Engram Entry and PrimalItem of the Spawner, add Blueprint path of new Rex instead of MEK, test it in Engine and it works, Rex spawns, custom Drops works as well.
I made sure to put everything into PrimalGameData (Additional EngramEntries, Structure Engrams and DinoEntries).
I cook mod and upload to Steam, subscribe and test in real ARK. This is where the problem comes in.

Everything works fine, is craftable, even the Rex Spawner. But when using it nothing happens, it only disappears.
I looked around for some time, double checked the stuff I did, everything looks fine to me.
But entering the Mod Folder in the ARK Directory, I find this
[ATTACH=JSON]{“data-align”:“none”,“data-size”:“full”,“data-tempid”:“temp_211108_1610207687995_266”}[/ATTACH]
https://forums.unrealengine.com/core/image/gif;base64

This is what should be inside:
[ATTACH=JSON]{“data-align”:“none”,“data-size”:“custom”,“data-tempid”:“temp_211110_1610207747575_672”,“height”:“543”,“width”:“439”}[/ATTACH]
https://forums.unrealengine.com/core/image/gif;base64

3 Files are missing in the Mod folder after upload to the workshop
-DinoDropInventoryComponent for the Rex
-Character_BP for the Rex
-Skeletal Mesh for the Rex
Without these files the Game doesn’t even know the Rex exists.
Is this upposed to be like that? Are the files somehow somewhere else?
If not how can I fix this?

To make it short:
After cooking the mod and uploading, 3 critical files are missing in the ARK mod directory.