not for nothing, but the next time this is going on, why not take a page from mom's book?

ie: be direct, honest and uncompromising ^_^

may as well, only have a few weeks left (which you could bring up if dragged into the fray), so why not just explain "calmly" that you take care of what you've done and if that's not enough they can go clean it til they're satisfied enough to suck it? (ok, i'm a bit cranky today, but the point is there...)