Interesting Full House Concept

[ThePortuguee]

I forgot to log the hand but here's what happened, I think on turn it's an intersting situation:

Six-Handed PLO Hi
Hero is BB with: 8-6-5-4
Villain is MP
Minraised pot, four way, flop is: 8-8-6

Hero pots, Villain flat calls, folds around.

Turn: (8-8-6) K

Hero pots, Villain repots.

I think this is an insta fold. Unless Villain is on a dumbass bluff, he has exactly: 8-6, 8-K, or KK. If hero makes decision to continue here, the only real play is to raise since he only has about 20-30BB left behind after a call. Given the apparent situation regarding Villain's holdings, it seems to me that, at best, Hero gets his money in a split-pot situation here. More likely, though, Villain either holds 8-K, in which case Hero is drawing dead, or 8-6-x-y, in which case, if x or y are bigger than 7, Villain is frerolling. As such, Hero is either splitting or losing all his money here, but he's never winning anything. So instafold, right? Thoughts?