Which is why an out of state businessman had to buy the Rams the last time, right? It doesn't matter how many HQs are located there, NFL rules require that owners be individuals. If the Rams leave town that means St Louis will have lost an NFL franchise for the 2nd time, there won't be another team there because the city is broke as hell and they aren't going to get voters to build ANOTHER football stadium. The Edward Jones Dome isn't even 20 years old and the Rams are demanding nearly $700,000,000.00 in renovations, which the city is refusing.
If the stadium isn't good enough for the Rams, it isn't going to be good enough for another franchise and there's no way St Louis is going to be held hostage by an NFL team for upwards of a billion dollars. That shipped has sailed.