First, KU only got a letter of allegations, to which they have 90 days to respond. Sanctions will come later, unless they successfully appeal.
Second, to the best of my knowledge, he is not enrolled anywhere at present, and cannot submit a waiver application until he signs a letter of intent somewhere. However, I think since he practiced with KU while enrolled and taking classes, he loses this semester to them, and the clock starts on his 1 year of ineligibility at the end of this semester (hence the Jan 2021 date).
My opinion is, if he is successful with a waiver, he will probably still not be eligible to play in games until this time next year, because of the time delay with NCAA waiver review plus the ongoing saga with KU. Although I guess he could try to apply for the waiver ASAP (after signing) and hope the NCAA will grant it quickly, assuming they have firm intentions of coming down hard on KU (which it seems to me is likely after what they just did to NC State & GT for much less serious infractions). But, does he even want to play starting in January of this year, and would Muss (or his new Coach) want him to burn a year of eligibility and only get part of a season?