TP multiway pot low board

That's why you should always 3bet with QQ, at least a small iso raise - you don't want to play QQ in a 4way pot.
And BB seems like a very disciplined player with 21/18 stats, he'll never call your overpot allin on the river, you can do that only against a fish.

bet v low on river like 1/3 ( ideally <$4) to get a call. Also 3bet pre as you're giving SB 3:1 odds and BB has 1:5 to call. I don't like 3betting with QQ as well but it has to be done sometimes.

Against a tight reg I don't mind a flat here in general. Against loose guy I could 3-bet this.

Flop seems fine, as well as turn - I could even consider a smallish raise on that turn card as the board seems rather safe atm, but best way to keep him in is to call perhaps.

As played, never overbetting the river. His hand looks more like a flushdraw, flopped top-pair or small overpair. Thus, betting 1/2-2/3 of pot would be fine here to get a crying call from him.

The bets of BB seemed very much like value bets. So, I put him on OP or set. I doubt he is folding FH otr. On the other hand he might put me on missed draw and call a small bet with hand like 88-99.

With a set that became FH he will not x river. You have to bet 55% pot max to extract value.