Would be a tough spot to bluff, imo.

Have to fold I think

Your play seems okay. Somewhat thin bet versus a decent player on the river.

On the river U have some AA (3combo), JJ (3combo), maybe some A2s(2combo) some flush KQcc, KTcc, QTcc, T9cc, 98cc, some AJ, some AK. So looks like no need to defend versus a raise, I don't think the population are too bluff heavy in that spot.

He can represent JJ (3), 22 and AA occasionally, KQcc, KJcc, maybe KTcc, QJcc so maybe ~7-8 combos for value, and need something like ~28% bluff, so not so much combos. Maybe with a better blocker like AxKc U can call, but with that combo U can fold I think.