Villain is 19/15 4% 3b and 50% fold to cbet. Should I be betting turn instead of check-calling? On the river we are in a ****ty spot, I don't think he would turn his 88,99 into a bluff here, any Tx in his range would also check back I think.

I would just call the river. Some players just like to call your CB on these super wet boards, because they know, fourth card to flush will make you life miserable when you have not any high card to flush - I do that often for example against weak players IP. So easy steal than.

In fact, what hand do you think he had? I would probably raise on flop with something like set of 6 or T (you will get paid from somebody with flush draw there) and likelyhood, thath he is holding something like 2 is really small. With 77 he would just check the turn behind probably - I would check his AF here to find out, which line he is going right now.

My gues is that he is bluffing with some missed broadways with one card to flush maybe or he has JJ or AT. I would just call the river.

Maybe I am just completely wrong, but thats how I would play this. Good to check HUD stats in these uncomfortable spots.

And to your question, yes, I would bet turn for sure. You will get paid from all of that FD and other weak hands like AT, or even some midle pair from loose players. Against agressive one is check maybe good option. But you must be almost sure, he would bet here with almost every hand in his range. If you check, V can just check behind and can got his flush for free on river.