I think so too, besides that the goblins have practically never appeared in the game until now (their last appearance was a scene where it was confirmed that they were alive but they are hidden in caves) so it makes sense to me that the theory that the antagonists might be goblins disguised as humans by means of a spell.The main antagonizing men are very goblinish looking. I bet it turns out they were using illusions and when its time to grow the tribe or something and impregnate all the women eventually.
But another part of me thinks that this is not the case, that the goblins are just a subplot of the game and that's it. Although I do want to see more goblin scenes with women.