I don't think it's easily dismissed since exfoliative cheilitis is a description of a set of symptoms which appears to have more than one cause.
Also mercury is present in more than just fillings. It can be found in tap water (according to the EPA: "the major sources of mercury in drinking water are erosion of natural deposits; discharge from refineries and factories; runoff from landfills; and runoff from croplands") It is also present in fish, usually the bigger the fish, the more mercury it contains as it "bioaccumulates." Salmon is one of the bigger fish not on the FDA's list of fish to limit your intake of.
I suspect improper mercury filling removal (after 10 years of having them) was a possible factor in developing my condition. Though mercury poisoning does tend to cause peeling skin elsewhere on the body and other awful symptoms, I am chelating the mercury (and lead) out of my system in order to rule it out.
I will get retested in December and if the mercury is gone while the condition remains, then I will be able to rule it out for myself.