A few years ago they changed the rules where you can’t block an assistant from interviewing for coordinator positions.
To answer the OP’s post, I’m leaning Robinson right now. I watched some film this morning of Waldron’s offense that wasn’t a YouTube highlight reel, and it wasn’t as impressive as some of the things I’ve seen from McVay’s offense. It looked like they were struggling as much as we did at times. Then I looked up their offensive DVOA splits and they were 22nd on third down and 30th in the red zone. No thanks.
I also find it interesting that Waldron doesn’t seem to be drawing any head coaching interest after three years in an OC role where he was being pumped up as the next great coach. In a league that’s hungry for up and coming offensive minds, that’s concerning.