Since she's going to a private school I believe all that is affected is their competitive balance number
Nope, you have it backwards. A transfer from a public to a private must sit out the the 2nd half of the season, unless one of the exceptions is valid.
You are allowed one transfer from a private, only to the public school district where the family residence is located. Without having to sit out any games. Reason being. What if you were paying tuition for a couple of kids at a private school and you lose your job and can no longer afford the tuition? What if both parents are working so they can afford the private school tuition and one of the parents dies? Should a student athlete be penalized for a family financial hardship?