No way the PA allows that.
Honestly whatever happens now it's fine. They got the extra season from holding him back for the 5 days to start this season. So if things get cancelled them for 2021 we start things no worse off than if we assume Pearson makes the team out of camp next spring (which he absolutely should regardless of service shenanigans that might've been in play)
Nate says the 5 days didn't bother him, but chances are it bothered some in his camp. If they had tried to hold him back for this whole season and also the next one at the start it probably risks significantly poisoning things.
We can "if" and "but scenarios for this season getting wiped out but honestly whatever unfolds now is fine.