I think we can c/c this turn. His range is mostly weighted twords overpairs, so we get enough implied odds on the river. I doubt he often manages to escape without losing at least one decent sized bet, even on diamonds. I find these guys whoare nitty preflop often wait around so much for overpairs that they find it difficult to fold them: the fact he's not full stacked suggests he's probably not great at ranging or hand reading so I think we're fine here and can have the best hand sometimes although rarely even on blank rivers. He's very unlikely to bluff missed fds or air on blanks so yah I like c/c turn as played.

I doubt we get him to 3 bet bluff the flop very often here after he c bets multiway given he's a nit. There's also like 1 combo of worse FD in his range, and he's likely to shut down on the turn with AK AQ etc and we can profitably bet the river. Don't see too much reason to c/r this flop. Think calling is probably more +EV.