My feeling was that if someone on her senior staff was inviting people personally to a major event… it had to have been approved by her right?

Aside from this being a relatively minor VIP event (it wasn’t a premier or anything, as far as I can tell this was just a regularly running broadway pay-for-VIP event themed to tie in to the show) I don’t think this really tracks - the goal of having senior staff is to not need to scrutinize each of their decisions, and although JK is many many awful things I’ve never seen her accused of micromanaging.