9 handed $2/2 NLH with people playing generally straightforward with limited 3 betting; I have no history with the pre flop raiser (V1) but I have played with the V2 (caller pre flop) in the past and he is capable of bluffing. Effective stacks are $300 and I am UTG with 9 9 (none of the suits matter) and I open to $10 (standard for this game) and I get 2 callers before BTN raises to $30 and all 3 players call so 4 players to the flop (~$115 after the rake)

10 9 8 rainbow: checks to pre flop raiser on the BTN and he bets $100 and I call, and UTG2 (V2) also calls ($415 in the pot)
Q still rainbow: checks around ($415 in the pot)
6: what do I do? I have $160 left and I am covered by both villains

In addition, any else I should have done prior to getting to the river? Thanks.

Check raise flop all in, your hand is very vulnerable, and the all-in would be for less than a PSB.

After flop action it looks like V1 has some overpair and V2 has a Jx hand.

Just check river, hold your breath and wait for V2 to jam.

Check/jam the flop. Not doing so is a big mistake.

Yup, I should have jammed on the flop; as played, I made the worse decision of all and jammed my $160 on the river and V2 called to win with A 7 (he was open ended on the flop) and got there with the straight on the river. V1 folded and said he had a big pair. I actually did not see the lower end of the straight and thought no one had the J; either way, I was wrong and learned another lesson in not slow playing.

You did otr what you shoulda done otf but he's not folding anyway so the lesson didn't cost you anything at all

If hero check/jams flop then V2 likely folds the bottom end of the straight draw. V2 is trapped between two players showing aggression. He should continue really tight there.

C/jam flop obv

As played c/fold if v2 jams, c/call if btn jams

Pretty standard ck/jam the flop given the texture and your hand strength.