Dentists joining or not joining wouldn't even be an issue if the program was properly constructed in the first place.
All the government had to do was plug into a long established system. I enroll, I get a provider number and plan number and I'm good to go.
When I had dental coverage through my employer, I gave my provider and plan numbers to the dentist and everything just worked.
That's 3 times what is being put into a federal housing program and AI already has people falling all over themselves to invest.