JJ vs donk and nit

BU is 38/23/1.0 with 15% 3b over 54 hands
CO is 14/9/inf with 22% steal over 60 hands

$0.10/$0.25 No Limit Holdem

Stacks:
UTG letsgetdangeros ($25)
UTG+1 floatingd ($30.99)
CO 3shipem__3 ($26.28)
BTN wreckless walsh ($49.65)
SB Hammans ($26.33)
BB Hero ($28.87)

Pre-Flop: ($0.35, 6 players) Hero is BB
2 folds, 3shipem__3 raises to $0.85, wreckless walsh raises to $2.25, 1 fold, Hero calls $2, 3shipem__3 calls $1.40

Flop: ($6.85, 3 players)
Hero checks, 3shipem__3 bets $2, wreckless walsh calls $2, Hero calls $2

Turn: ($12.85, 3 players)
Hero checks, 3shipem__3 bets $4, wreckless walsh calls $4, Hero calls $4

River: ($24.85, 3 players)
Hero checks, 3shipem__3 bets $18.03, wreckless walsh folds, Hero ???

I thought about folding turn, I thought about raising turn, and I thought about raising flop.

On river I don't see him having very many value hands because some would bet smaller instead of shove and AA, KK, maybe QQ sometimes are raising pre flop.

Thoughts on all streets appreciated.

I would checkraise/fold the flop here because there are tons of draws on the board and any card completing these draws + any overcard to your J's are going to completely waste the SD value of your hand. Again, don't take my word for it, others better than me are probably going to explain why this would be retarded...

Your opp's bet sizing + donking flop are really weird. Have you seen him do that before? All I can say is the fact that he is tight, calls a 3b OOP and small donks the flop make me think to a medium pocket overpair like 88-TT, or maybe a flopped set (?). I doubt he'd do that with a draw only to be raised out of the hand (which BTW probably makes 88 less likely). There is also always the odd chance that he flopped a straight, but then why would he wait for the river to get it in and not bet more on previous streets? Then maybe he would play a flopped set like this and he is trying to induce a raise, who knows?

Actually TT probably makes most sense, he plays it carefully early on, then hits a set on the river?

I think it's a fold on the river. Unlikely to be a bluff vs 2 I would say.

thoughts on their ranges?
river and villain beats QQ so that's trivial.
earlier streets are interesting.
flop is pretty bad to be check-calling...

I think maybe 4b/get it in might be better here PF??

For their ranges:

I think CO is going to call wider than he normally would
1. Because BU is a loose 3ber
2. Because he's getting better odds after I flat the 3b

So, I think his range is like AQ, KQs, maybe stuff like QJs, JTs, and then pp's.

BU could have lots of things and I don't yet have a read on what kind of hands he likes to 3b. If he doesn't 3b suited connectors then its likely he missed this board I think.

I don't think CO can have AA, KK because that would probably 4b PF most of the time. Also, all the draws missed, so what is he really shoving river with? Just sets?