I love these corals, I have two different colors in my tank right now. If i was put into your situation i would probably just try and get the separated stocks together as close as possible and they might form back together with some time. However,

Leather are not the easiest to get stuck after fragging but with the fragger in me i would think about separating it into two peaces. But i dont know the actually size of it so i would hate to suggest that and the end product would be the size of a dime. But good luck with it i would say it will be fine in some time.