Considering how much money these sites seem to bring in to the site owners, I don't see why there can't be a mod or two or three who are paid by them to attend shows and do the job of moderating. If they are missing shows that they are scheduled to moderate, they would then be treated as an employee who didn't show up for work. If problems in chat go unaddressed (ie, the mod is logged in but away), the mod would be treated as an employee who is not doing his/her job. This would do away with the "random chance" that mods will just happen to be in chat for the model's shows -- if you are paying people, then you have more ability to call the shots.
Scheduling a paid employee would do away with the random chance that a mod will actually be in attendance. A simple contract is all it would require: if you do your job, you get paid; if not, not. It seems that this would be worthwhile to the owners, given that the models would be happier and put on better shows, and the attendees would be happier and encourage others to join.
I really need a new fucking signature.