The only way this would work is if the Rams decided to let JG go (don't know the terms, but almost for sure there is guaranteed money involved). Why? Because the Rams are not going to keep 3 QBs on the 53. That is simply poor roster management in today's game.
Rather, you keep 2 QBs on the 53 and 1 on the PS.
The other reason? Wilson has been a failure. Why would the Rams take on a failed QB who has never had any consistency in his game?
Another reason? McVay has never shown himself to be a developer of QBs. He couldn't develop Perkins or Wolford. And he has no history of developing QBs, nor the patience needed to wait for QBs to develop. Goff was a perfect example of having no patience with a QB that still had some development potential.