When my daughter was a recruit,she did base some of her decision on the coach and how much playing time she’d get. Of the schools she really considered, only 1 coach was still at that school when she graduated (the school she picked). One coach had left before my daughter would have even started (like OP’s coach) and that school had 3 coaches before the end of her freshman year! Daughter’s coach stayed for 4 years (the time daughter was at school) and left with very little notice.
It happens. It happens often. Your daughter met the team and liked them. The old coach felt she was picking a strong team and that’s probably still true but there is no way to know if some superstar player will walk on to the team. Your daughter has a really good chance of making the team.