What is a good strategy here? HU PLO with 5/1 chip disadvantage against someone with -40% ROI for last 120 days on OPR.

Blinds 400/800 and 20K---100K to start HU so some decent room to play.

Every time I raised pf or the flop he folded. He limped every button and min-bet every flop whether he was in position or OOP.

I felt like I was getting abused because I was clueless how to play against him.

**** it dude, let's go bowling.

Keep raising preflop regardless of position. the blinds are meaningful enough that him folding isnt terrible, if youve got real junk you can fold to aggression, and if he just calls and you hit a flop you can double up. Youre never so far behind PF in Omaha that successfully stealing 40% of the time and seeing flops 60% of the time can be too bad when youre clawing your way back. You need to build pots for when you do hit.