For CA to pull from their own coaches, they would have to have multiple coaches willing to move across country. Also if the coaches are willing to interview and move, they are obviously being offered something from CA that they are not receiving from their current gyms. Coaches leaving happens all of the time. Sometimes because they are done coaching, sometimes for a big gym, sometimes not... this is not a matter of CA doing anything unprofessional. This is nature of cheer as a business.
I don't know of many gyms at all except for very small ones, that the kids are guaranteed the same coaches throughout their entire cheer life. They may have to deal with new coaches at their current gym for completely different reasons. Yep it sucks if there is a close bond but that isn't because CA is doing something "wrong" or unprofessional.