I do sometimes, in speech, end up putting the "-en" endings by accident on irregular verbs, when speaking in a hurry: "I've just boughten them..." without fail, I stop and say "boughten?... uh... bought" and continue, more slowly.
Of your example, it's easier to imagine saying "caughten" as with my "boughten" -- maybe because it rhymes withour our American "gotten"? I can't iminage slipping on the "sold" one though. And it's impossible to think of it showing up in writing this way! Unless the author enjoyed pointing out the speaker's grammatical, unintentional faux pas.
I know you think that Americans just don't use the present perfect, but really and truly, we do. (Sometimes, as these examples indicated, we even overly apply that regular participle ending.)
I imagine the BrE speakers don't make this taughten/caughten/boughten slip because your particple of "got" isn't "gotten."