Quinn is drafting him for that 3T Golston tweener role. Fehoko is a brawler against the run, although light in the pants for brawling NFL guards. I think they want him to be a sturdier version of Osa and Golston.
IMO, there were better directions to go in the 4th round. Osa and Golston are both pretty low-impact players... okay for 3rd rounders, but definitely no home runs. And both are very good athletes for their size. Sticking a very average athlete in that role... man. I don't see it working out.
When you break it down, Fehoko's floor is the XFL and his ceiling is like a Justin Hamilton, 20 snaps a game backup DT. That doesn't measure out to a 4th round pick. I would have taken him like 6th round or 7th.