Had plumber over to fix a stoppage today. He aggressively used a large snake/rooter for about an hour before he noticed our house used a grinder pump (I didn't know this as we just moved in). He now says the pump is broken, but I'm a little concerned that his snake/rooter damaged it...as it got stuck several times and he was jamming/yanking it very aggressively. How likely is it that he could have damaged it?