"DNA that most folks use is autosomal and only relevant to about 4 generations so this is much too early for that to be of any use. "
That's actually quite untrue.Autosomal can go back as far as 11 generations! On average only 1/2048th of it survives from a person that far back. And, of course for two random people to match someone that far back the probability is that squared (barring cousin marriages). But ... if you have shown that you know segments that come from that person, proven by triangulation of lots of people and also by Y-DNA and/or paper trails, its the 1/2048th that mattters. The probabilities are such that a goodly fraction of people who have autosomal dna in that line will have enough (say >8 cM) that they are reasonably reliable, and a few will have as much as 20 cM.
In the Clan we actually have such a situation. We established several men whose Y chromosomes matc. Several claim the common ancestor was the person John MacDonnell "of Moyne, co,. Clare, Ireland, 1670-1704". John is well attested historically but there is, as far as we can tell, zero paper connecting him to America. There's an early 20th century book that does ... with no reference.
Of course, the Y DNA is proof that such a person existed, just not what his name was. We DO know, 100% sure, now 100.0000% sure thanks to the Telomere-to-telomere project's reference Y chromosome (*), that all these DNA testees descend from John 1st Lord of the Isles, d. 1386, who had four sons with well attested paper trails. Three of those are accounted for with DNA and perfect paper trails to the present. The fourth, as I said, has a great paper trial all the way up to John "of Moyne"'s father, passing through the famous "Sorley Boy" MacDonnell.
We know the purported paper paper trails of several of John's relatives in Ireland (his wife and her parents and siblings, as well as those of the wife of one of his sons).
Thanks to Gedmatch (and only with the tools Gedmatch supplies is doing the finding not a hoplessly slow task) I have done a statistical analysis of matching autosonmal segments for those people with paper trails. Some of them are in America, in the correct places where John's purported descendants lives, while others are for living people still in Ireland. The analysis shows that the probability of a match of randomly chosen people with ancestors of the correct surname is low not non-zero.The probability that a person named MacDonnell or McDaniel with matching autosomal DNA that does not triangulate is much higher if the person is living in county Clare than other places in Ireland, and vastly higher if living in the three towns where John was, i.e. Moyne, Kilrush, Kilkee and Ennis. The same is true of people surnamed Frith, John's wife's mother. Those matches go back to the 1630s.
Do note that the average age of the parents in these lines is well above the overall average of 31 for men, especially starting about 1810. In my own line its above 40.
I propose that all these statistics are good enough to prove, from the autosomes, that the purported lines are correct. One additional statistic: the segment size distribution of all matching segments starting at 5.5 cM for all the people who have good paper trails is exactly correct compared to simulations. The segment size distribution for randomly chosen matches is biased very much to tiny segments. (Of course, that we have triangulation formany of the expected people is an even better test.)
I should add at this point that I spent over 1000 hours doing all that work. It would be a lot less if every site had tools as good or better than Gedmatch. Of course its absolutely impossible at Ancestry.
This of course has little to do with Wallace, but lots and lots of men in these lines fought with him.
(*) the marker that delineates him, CLD56, is neither an STR nor a SNP, but rather a delete 9415 bases long
