He had opened from utg+1. I think from how he was playing we can eliminate all worse flushes. Simply because IMO the only worst spade hands he would POSSIBLY open is

or even slimmer

. I am 99% sure he would be flop with these hands.
From how he played the 99 hand as well I think there is a <1% chance he has a set, especially as turn I'd like the wettest card ever I doubt he ever c/c that and if he does have a set I 100% think he would check call river.
Although only a 1 hand sample, the 99 has lead me to believe he would also bet all Jxss on flop.
Taking all this into account I can't really see how im winning unless he has just lost his mind. If he has I think he would just pile river, not check so that if I bet I'm getting an ever better price on my river call.
I get what people are saying bout AA and defo agree. Just think he would be far more likely to just pile AA on river as well as opposed to check jam it. If doing this with Ax As is going some way to making me think he was turning his hand into a bluff, which I don't think violin is capable of.