Download the original game and login to your main account, after that backup the data only.
Delete the original game and install the mod, restore the data and you'll get to play with your main account.
I managed to do it but i don't know if it'll sync with google play account because there's no longer a little pop up at the top of the screen when logging in
I used Swift Backup but it should be possible with any tools that can backup apk's data, ohh and you need ROOT probably, to backup data
Thank you, this worked, I used Titanium backup.