[mimimomo]

Was a full blood panel done? I'm wondering why your vet would say anesthesia is not good for him w/out looking @ blood work. Blood work would give a good indication of how all his vital organs are working & give the vet an idea of how the dog would handle anesthesia. Senior dogs need this done every 6 months anyway.
I know the what if's are scary & there is def some risk involved every time they go under. But, tooth decay is scarier & periodontal disease can cause harm to the major organs & bring on disease.
A 2nd opinion wouldn't hurt & honestly, visiting a reg vet & a specialist is like night & day. I've been to a cardiologist when Momo was a puppy & they were able to take care of the issue on 1 visit. It was expensive, but my repeat visits to the vet (4 different ones) w/no answers for months were more costly & stressful for both of us.