I'm sorry I don't know anything about this.
But I noticed no one had replied to your post. So I thought I would.
My wife & I used to have dental insurance through her work. When she retired we talked with our dentist about it & he mentioned the things you mentioned in your post. There are waiting periods, the plans are expensive, & there are things they don't cover. He said most of his patients who don't have employer-sponsored dental plans simply private pay. And that's what we decided to do. Perhaps if you have a particular dentist you're going to be seeing, you could talk with the staff in that office about this? Good luck with it...