Yes it is a sad day. I did think of the necropsy, but there isn't a "good" reptile vet around here. Even then they may not find anything. I may try again again in the future. I always thought it was odd that only heard him croak twice in his life time, he usually only chirped when you picked him up. I actually think Kermit was a female, but I never had it confirmed.
Thank you for your kind words. Good luck with your "Zoo".