I highly doubt the girls would be peaved about her choosing school over DCC. I get where you’re coming from, but Milan seems responsible enough and it probably just came down to Business school being much more than she thought originally.
And if Emma is filling her spot, formations aren’t changing anyway. The most that changed was Kelsey moved to her spot in the small group. Formations aren’t rocket science. I think the show portrays it to be this super intimidating difficult thing when it really could be moreso stress in the beginning and doing a few different counts.