That's true. But you overlook one key point.
It's true that teams would rather wait Dallas out and force them to release Romo after the June 1 cut-off (when the cap hits from cuts get pro-rated against 2 years of the cap rather than simply accelerated).
So, of course, the smart thing for any team that wants Romo will wait, right? Well, not exactly. You see, they
would wait, but for one thing: they know Romo wants to come to Denver. So, if Romo gets a visit scheduled in Denver, he probably won't leave Denver without a contract, because that's his desired landing spot.
So, how do these teams force Romo to come play for them when he'd rather be here? They have to trade for him. Then they hold his contract. He can re-negotiate his contract, and refuse to be traded to that team of course, but would he? Probably not, especially if it were a huge hassle and would give him a bad reputation. And doubly, especially not if the team he's traded to pays him a boat load of money.
Did I mention that a Boat-Load of Money is usually not something you refuse. "Mr. Romo, I know you'd like to play in Denver, but they can only afford to pay you $8 M a year! That's backup money! Why don't you come to our crappy assed team that has over $100M under the cap we need to spend. We'll give you a ginormous contract, so big you won't be able to lift up the check."
"No? You'd rather throw away $16,000,000 a year to come play in Denver Mr. Romo? Great! Welcome to the Denver Broncos!"
Somehow I don't think that is very likely. I think he will swallow hard and think to himself: "you know, I'm scheduled to make $24,000,000 this year and I'd kinda like to get that and not take a $16,000,000 pay cut. Thanks, but no thanks."
What would you do?