How would I go about extracting models from a pc game?

[Garamonde]

Well, you can't just submit the .OBJ with no textures with it or anything.
Please read the submission guidelines, as well as this, what you could call a "model quality guide". It explains most everything you need to know about making your models acceptable on TMR.
Also make sure that the textures are in the same folder/directory as the model/s they belong to.
And one more thing, I know you've been through a lot already, but it would be very much appreciated if you could provide a .DAE with the bones and rigging too since it should be possible with the models being .PSK and all. It'll make your model much more useful for everyone.