The entire Mique Juarez saga is kind of weird...
Spring 2016: Mique Juarez signs with UCLA
Summer 2016: Juarez stops showing up for practice. Coach Mora described it as 'excused' due to personal issues. (Juarez is quoted as saying "It was just too much pressure")
2017: Played in 12 games.
2018: Injured in the 1st game against Cincinnati. Stopped going to practices in October.
Since then he's been working out on his own doing drills he remembers from practice. He works out alone at a student gym or soccer fields. he isn't working out with any players/friends.
It could be the 'Forced Medical Retirement' was a way for Coach Kelly to clear some dead weight (P5/Pac-12 rules say a coach can't pull a scholarship for poor performance or attitude). Kelly has been cleaning house... UCLA currently only has 70 scholarship players on the team (of the 85 allowed).
I don't think Whittingham would agree to a player joining his team if the doctors won't clear him. It could be he's just giving a troubled kid a 2nd chance.