Don't you want the BB in the pot with his tp tho? Without doing the maths it feels like this would be better for your EV than trying to fold him out. When you shove he's still calling with draws better than yours anyway. If you call and the BTN shoves, which he will, then BB may easily donate to the pot with top pair. Your smallish drop in equity (when BB has a made hand and stays in the pot) should be made up for by him putting more money in, I think.