Just want to make a point (and politely disagree with Franchise on something), this is not "UM Admissions" in the traditional sense. Normally, for undergrads, they go through the "Admissions Office" as we tend to know it.
But "grad school" has separate admissions processes. The Med School has its own admissions office. Same with the law school. The MBA program handles its own admissions. And at the other extreme, there are some grad programs that are so small, that they don't have a full-time admissions office, it's just professors and administrators who handle the decision-making.
I have no inside information as to what grad program Williams may be applying. Therefore, it is hard to say what the processes, academic standards, and decision-making timeframe may be.
Ordinarily, Franchise is correct on this, if the football program has a signed LOI from a grad-transfer, we "make room" in a graduate program somewhere. But if you are also trying to comply with blueshirt rules by "not recruiting" a kid, and he has to apply, get in, and pay (initially) on his own, it can definitely be a bit more challenging to be admitted.
Miami has never enrolled a blueshirt, let alone a grad blueshirt. We don't have a lot of experience, and Covid-19 isn't really helping in relation to the calendar/decision-timeline either.