Your point makes absolutely sense, but it's difficult for me to believe they will "sacrifice" him.
Vingegaard is they're main rider for next years, it would be really bad sacrifice him now, when he is still young and can win more in the future.
It could be a lot of factors going into the decision;
He could have been not that injured,
He could have recovered faster than expected,
He could be recovering slower than expected,
The team could think he can come in with average form so to speak and ride into top shape at the end and win,
Team could not think highly of the competition bar Pogacar and think he has a chance no matter his shape since Pog has the Giro in his legs,
Team/management could be worried this season would be deemed a failure after coming off the best season a team has had,
It could be PR so the others don’t focus on Kuss and Matteo if Vinge starts,
It could be the other forum related,
or it could be they will try the Tour and if push comes to shove change focus to the Vuelta.
There can even be more than this.
I think it’s a combination between of multiple factors. If he does win I also think they’ll push this hard like Armstrong and LeMond coming back from their setbacks.