It is another of those examples of putting a bad interpretation on something and to hell with having actual evidence, isn't it?
We do need to work out whether her house, complete with her child's deeply offensive bedroom, is their work environment or not. I would say not: unless they were working in it which I rather assume they were not, since they are dancers and need a certain sort of floor and space to work on and in that's not a workplace. So if she got drunk over the meal, for which I don't think we have evidence, she was not unprofessionally getting drunk at work, any more than someone getting drunk with fellow workers at a pub would be. (Unless they work at that pub.)
Stupid to trust these tiny-minded idiots, certainly; but then, what is the use of a dance company if some of its members cannot be trusted? It isn't a coherent group at that point, is is a disparate rabble.