It's a super tough spot on the river and honestly I would probably find a fold as well. Like it looks like he just has a flush, I mean what hands is he bluffing with? I can't think of one. (His call on the flop is terrible IMO so I wouldn't expect him to have the bare Ad ever), but props to him for at least turning it into a bluff like he did. You have Qs8s so you obviously don't block any diamonds. I don't like shipping turn because its a way ahead, way behind spot. You're almost never getting called by worse (AA w/Ad or KK w/Kd maybe the only hands), but I forgot what the action was pre so maybe he can't even have those. It sucks though because you're like at the tippy-top of your range and this is almost the best hand you can have given the action but it's just so hard to give the guy a bluff in this spot.