Leaders are going to plan and drive. The BYU brand in the state in an effort to diminish all other competitors. They are not looking for a symbiotic relationship. That only changes if Utah gets an invite. If they don't, no dice.
Regarding Indy. Not likely. They don't have the infrastructure to make that work. They might do it as a transition year between conferences, but not willingly. Utah is part of the debt to build strategy that most college athletic departments engage in. BYU is part if a small group of colleges that don't do that thus don't risk being upside down financially.
Finally P status can be fickle. We've seen what can happen. So my argument stands.