I think you should jam river.
He just checks all his hands with showdown value, and would probably call a shove with any hand he value owns himself with when you check the river.
He would likely ditch bare diamond draws to this big bet on the turn, and doubt he turns combo draws into a bluff too often.
River is a sigh call, as he jams worse sets and perhaps some 2 pairs he has played passively, and a small chance he could be spazzing, but we def see a flush or JQ here plenty.
Defo this. didn't realise we checked but yeh you will go insane if you only value bet nuts on the river, easy after a few bad hands to get in the mindset of 'oh i bet they got it' and just tilt fold.