I agree with stormwolff. I recently removed staff priveleges from three GMs who were not following simple rules I laid out before they were brought on board. It's not easy or fun to deal with booted staff members, as they typically get exaggeratedly defensive and often make their own case worse. But were I in your position, I would not allow another chance for these GMs. It's not worth it.
And I agree with Quantos. I was typing up my reply when he posted.
Staff who won't abide by your rules or wishes should not be staff any longer (in my opinion).