It was inappropriate, in my opinion, because of where it was done. There was no reason for it and if parents are their to discuss the schooling of their children - then why did this administrator feel it was okay to suddenly put on a show for them?
The meeting would have been one much like a business meeting in my opinion, education is serious business and people need to know those who they are leaving their children to, are upstanding and competent adults. Dressing in drag and performing a "show" that could be misconstrued by those who saw it, as a strip tease act - was inappropriate. Apparently a few shared the inappropriate opinion given the gentleman is now under "investigation".
As far as the punishment is concerned for what he did - suppose we will have to wait and see if there will be any at all - the article did not say.