Just to make this clear:
Sackbot death DO NOT count towards level acing.
However they DO count against 10 level ace streak.
But I can confirm that during my streak when I did the first sackbot level when they ran away from me, 1 sackbot fell in fire and it didn't break my streak. But during the level where you have to use bee to transport sackbots, several died with electricy, plasma and one got crushed and it broke my streak. So I'd say its pretty random if it breaks it or not.
No blank friend requests, please. They will be ignored.