I understand, my parents had different values than me regarding animals when I was dependant on them.It's not so much the price, she just thinks the idea of getting a chicken necropsied is strange and she wouldn't agree to taking time out of her day to bring it somewhere to get necropsied. I actually asked her about it once before when one of my parakeets died mysteriously, so I already know the answer.
I agree now that it probably wasn't mold, I went looking all over this morning and I didn't see anything unusual. I checked their food thoroughly and it was fresh and dry, so I honestly have no idea what it could have been. I'm not sure if there are any poisonous bugs in maine that he could have eaten? seems like a longshot. I was thinking maybe they had spilled some food and it got rained on and developed mold, and he ate it before i could notice. But they don't usually spill much and maine is going through a drought right now, so that seems unlikely.
I'm glad he didn't suffer long and hope that you recover soon.