I ran a "worst case" on poker stove, using swiggidy's estimates for opponents. The only "bad" hand included is KQ, so it seems like Hero's equity HAS to be better than 33% here.

541,800 games 0.018 secs 30,099,999 games/sec

Board: Js 9s 3c
Dead:

equity win tie pots won pots tied
Hand 0: 31.895% 31.56% 00.33% 170997 1809.00 { AsTs }
Hand 1: 13.567% 13.23% 00.33% 71698 1809.00 { KQs, QTs, T8s, KQo, QTo, T8o }
Hand 2: 54.538% 54.54% 00.00% 295487 0.00 { 99, 33, J9s, J9o }