Conflict resolution

Scenario. New boss I've already had a conversation with about keeping me in the loop so i know everything that is going on within my scope of responsibility.

Cut to this weekend when he held an entire event within my scope without telling me it was this weekend. He used to be the go to guy for this sort of thing at corporate, but there's a difference between theory and practical.

Now there are holes left and i'm struggling even more to have the misogynist douchebags who report to him listen to me on anything.
I can clean up the mess, but ideas on how to help it from happening again? He doesn't seem to see the problem. I mean, he told me it was going to happen, but never gave me a date just the impression it was months away and planned the whole thing with the douchebag brigade. I could have helped prep them and learned stuff myself. But not if they don't tell me.

I'm not great at this brand of confrontation or manipulation, whatever is needed.