For the love of neeps and tatties, he STILL hasn't told me where in Burke's Peerage there's any reference to John Stewart other than as a son of Duncan Campbell who DIED WITHOUT ISSUE.
He STILL hasn't told me if he accepts that Janet Gordon was the daughter of the 3rd Earl of Huntley, in which case he isn't descended from James IV.
He STILL hasn't explained how he knows that Sir James Campbell had a daughter called Mary. The only child of Sir James Campbell I've been able to trace on the internet (not having access to a copy of BP, but I'll check this later) is John Campbell, who later became the 1st Earl of Loudon. Of course there can't possibly be a reference to the "Lady of Lawers" in BP because it was Charles who transformed her from an unknown Stewart of Appin into a Gordon.
As far as I can see all Charles has is evidence that a John Stewart, baptised in 1645, was the son of John and Mary Stewart. Hey presto, simply transfrom John Sr into the shadowy John Stewart of Appin, provide Sir John Campbell with a daughter called Mary, ignore the semi-folkloric aspects of the original story and there you have it - PROOF strong enough to edit a Wikipedia article (but not strong enough to cite your sources).
ETA: Oh, FFS, Charles. That link is essentially a search engine and I have no intention of doing any more of your work for you. If you have any solid evidence, post it yourself.