Somewhat complex question

Hi guys,

Is it possible to transfer Hay Day from my iPad (Game Center) to another account on the SAME iPad?
Because we've bought this iPad for our son and my wife was playing Hay Day under my account.

Since we are officially divorced, the iPad stayed with my son. My wife wants the progress of her Hay Day saved under her own account.

More information: it is connected to the Game Center with iOS 8.x, connected to my Facebook and my Google+ account.

Can it be transferred? If so, how do I do that without losing progress?
I hope this works, because my ex-wife is on level 64.
Thanks and regards,

Ronald.

I have an android and they use google play. I changed jobs and my email was for my job and I didn't realize that it was on that Google Play account. So I emailed Supercell and they transfered the email which changed the google play. I don't know if that will work with iOS or how it is set up.