The pictures just aren't very clear, but It seems too large to be Lymphocystis, but maybe? Is the fish still feeding? The video is the clearest image, but I still can't tell if it is bacterial or viral (Lymphocystis).
Lymphocystis commonly begins at a site of an injury, and with clownfish, that is often the mouth. There is no treatment, but Lymphocystis will go away on its own, but one risk when it develops on the mouth is that it can impair feeding.
Jay