Did you happen to notice who manufactured the G2SE? If it was manufactured by Aurum Cantus you could call them and ask if they are compatible.
To be honest, if they were my speakers and I could not find out the information otherwise, I would ask the dealer or call Proac directly, its not like you owe them anything at this time. Buying a new amplifier is a big deal, especially as a number of persons aren't so sure that it was the problem. It would be nice for you to be able to run the speakers in the meantime with a less expensive potential outlay until you have it all sorted out.