Yeah my doctor is a Psoriasis Specialist, and has looked at my biopsy slides with his Pathologist and they both believe that this points toward psoriasis. So I am on the most aggressive psoriasis medication/routine possible so we will see.
As for your doctor, Im not surprised to hear he/she didnt think it was psoriasis. Some doctors still dont recognize psoriasis of the lips as a real thing. Which I find absurd. But my doctor told me that Lip Psoriasis most definitely exists but is extremely rare.
Fortunately my father is one of the most respected surgical oncologists in the nation, so I am blessed to get appointments with the best medical professionals in my city. And unfortunately a lot of the doctors that people describe on here seem quite incompetent, and arent of much help. But Im using my position to its fullest so Im hoping we can figure this thing out.