I found this hand quite challenging and solver didnt give me answer.

Firstly about the hand: I've studied similiar spot last week so I knew that my flop size is good and my hand choice as well is pure bet. Obv. hard to mess up high EV hand

My opponent unknown reg, vast majority of the pool to be on a tigher side(especially preflop) postflop tighter than 200z as well.

And what PIO brought light on : Turn even though is fine for him (51% equity) he just not betting anything (for block as well, few % at best) and pretty much across all flush turn card he doesnt bet more than 35% (mostly small size)
So we are playing non existed line in equilibrium