David Tepper has a net worth of 18.5 billion dollars. He can find a loan from a bank to finance his brand new domed stadium that can host a Super Bowl, if that's what he wants.
The issue I see is that everyone wants domes so they can host the super bowl (and monster truck rallies or whatever but mostly the SUPER BOWL!) However if every team has a dome and the NFL is equitable and doesn’t just say ‘f-you, cleveland. we are going with New Orleans, Vegas, and Dallas every year’ then you get one super bowl every 32 years. The economics of it seem off.