Although it is easier to diagnose in person with a veterinarian... This does "appear" to be a burn. Even though basking/spot lights may not have the temperature extremes as measured with a thermometer, there may be focal light points that will magnify the light. Easy way to see this is to...
Here is another resource for reptile medicine specialists with the American Board of Veterinary Practitioners (http://www.abvp.com/diplomate ). There are a good number of veterinarians who see a lot of reptiles, but these are the only ones who can call themselves "reptile medicine specialists."...