c/r seems good on river, but i think another option is overbet shove? On the river i think his calling range is pretty much the same if we c/r or shove, so we need to consider parts of his range that may bluff when checked to, and parts of his range that may check back instead of call. I can't really see him ever really bluffing here without like Ah6h or some weird hand like 8h5h, but then again i don't think his bluffing frequency is very high because lolloosepassive fish. im thinking that there are some hands that he may sometimes minraise turn with some AT or somehow gets there with an overpair and decides to check back river. You're def losing a lot of value by just potting river tho ;(