Some more information about the situation (table dynamics, stage of the tourney, buy in, tournament type) would be helpful. But you have to consider the fact that a 19BB stack has just flatted in front of you, that line generally seems super strong, so unless you’re playing against micro fish (5k gtd, I suppose that’s possible) I’d say your A9 would likely find itself dominated, and someone iso shoving could be exactly what the HJ is trying to achieve. Anyway, that’s just my 2c worth.