I have no Darwin’s Ark dog links to provide, but have you seen Embark’s page about American Village Dogs? It has links to the full Embark results for a dozen randomly selected dogs who’ve tested as 100% AVD with them, as well as for a dozen AVD mixes they’ve tested.
I sometimes browse a subreddit devoted to sharing DNA breed test results, and “rez dogs” posted in there not infrequently test as partly or entirely AVD, which as you say makes sense. Others test as multimixes of various breeds, or as mostly or entirely “Supermutt” (i.e. matches neither any known village dog populations they have on file, nor any pure breeds on file, and therefore probably does descend from purebreds but it’s too far back for reliable matches).