I don't think this changes anything.
1. Why does it matter who your 3rd QB is? Its not like DiNucci is a stud who they're sitting. Its just swapping out backups of backups. Wouldn't even move the point spread an inch.
2. I'll believe they're tanking when Andy Dalton is healthy and they opt not to play him. That's the real signal. As of now, all they're doing is shifting around deck chairs on the titanic.
I know this is sort of tongue in cheek, but "tanking" is actually throwing in the towel. Like intentionally not putting your best players on the field with the desire to lose games. Cowboys aren't doing that. They're putting their best players out there. Its just many of their actual best players are either injured and can't play, or aren't playing well to begin with.
If I'm Dallas I probably don't want #1 anyway. I'd rather be in the #3-#5 spot so I can get a boatload of picks on the trade back. Its pretty blatantly obvious to everybody that Prescott was the only thing holding that team together. They should pay him whatever he wants, cut the dead weight of some of these horrible contracts they gave (like Demarcus Lawrence) and trade back from a top 5 picks and get a great haul for short and long term.