[LunarBerry]

Yeah, I agree with Wylie's Mom, going about it I'd definitely just say to her it's not working out, after she's not having them in her care, and then explain to her why. Like everything that bothered you, in a very neutral tone. This girl may be in doggy daycare services, but she seriously needs to work on her work ethics. Thank goodness, though, that you are taking steps to remove her from your service.
Anyone of my family, friends and coworkers, knows how I am about my furbaby and knows I'll go off on them if they don't do right by her. Granted, I'll try to be nice about it first, depending on how bad the situation is, but if it's ignored or the situation was bad enough at first, then it's on. Hope you can find your furbabies the sitter they need/deserve.