Essentially, if your daughter takes premed classes at the CC, she will be considered a less competitive candidate by some med schools and won’t be considered at all at other med schools.
So, if her goal is med school, she’d be better off not taking her premed core classes there. I would imagine that taking sociology and psychology over the summer would be okay, plus “regular” gen eds, but she’d waste a lot of time since UCs only take upper-level transfers who have completed all their major prereqs at the CC and she wouldn’t be able to take her “premed core classes” at the UC at all. 
It’s better to avoid that, except for one or two classes here and there, in complement to other classes taken at a 4-year college and where clearly academic performance is not in doubt.
In short, if your daughter is serious about med school, the current plan isn’t a good one: she’ll save a year… and be stuck afterwards.