Sorry to hear that
. Electronics are pretty straight forward for the most part. Once you have crossed the upper temperature threashold, you can pretty much count on the fact that the gear will fail. Even if you do get it running again it probably will not last for very long
. You may even cause damage to the new ESC, or other components in the process
. Once you over temp any electronic compnent it is degregated to some degree and will never operate at full capacity again.