Although Milton needs a lot of work, I don't think the odds favor Grier being QB2.
Grier, a third-round pick in 2019, also got a late-season start his first year, which he spent as a third-string quarterback, and did not look good at all, unlike Milton. He also started the next week and threw for 4 yards and a pick-6 before exiting the game. He has been a practice-squadder or third-stringer ever since.
There's is nothing on his resume to say that he should be No. 2. Milton at least has the fact that he looked excellent in his one NFL start. He already has accomplished more than Grier.
I don't disagree that they need another quarterback, because I think Grier needs to be upgraded. However, at this point, I don't think it needs to be a veteran. I think we should see Milton play before deciding that.