Pumping up a big pot on the river without the nuts

The betting patterns of your 2 donks is really interesting here. MP is aggressive early with the A high board. Pretty easy to put him on it. When the turn A falls, he is probably "calling" to get overcalls - big mistake. BB is still hanging in there. spade on the riv - MP is calling down Aces (at best) and BB made his flush. I think you are good, and the turn is the inflection point as to who is second best. Neat hand.