I think Butler taking the 3 was the right move. The Heat were losing the whole game, were on fumes, and it felt like that run at the end was their best and last punch, so going for the 3 and hoping for a stop to win the game was a better decision than getting the 2 and then having to win in it OT (since Boston more than likely plays for the last shot in regulation if the game is tied). I am generally not a fan of hero ball, but in that scenario, taking all things into consideration, I think Butler taking the 3 gave them the best chance to win the game.