Hello,
Wow, that is an old dragon indeed!
As suggested, try using the raw unpasteurized honey or manuka honey on that area initially.
I don't think it would be gout, but you never know. How much protein does he get weekly?
It almost looks like some type of insect bite too but not sure. Sometimes gout can cause areas
of swelling similiar to that, which look like an infection.
I am glad to hear he is alert right now which is a great sign. I hope you can get him into a vets
soon, to be sure it isn't a bad infection starting.
Let us know how he is doing.
Tracie