When I was shown to be a DNA match with Lisa 6 years ago we communicated briefly, but didn't know on which family lines we matched. And we only had a couple of co-shared matches who didn't respond.
We have a few more now, I can see a much wider picture and I think that the match ( 5 generations to MRCA) is going to be along my line with unusual surnames and in my tree will go back to around 1790's- 1800.
Which would hopefully answer Lisa's original query, and confirm a comment made on this thread. I don't have a lot of close family members who have tested, which on Gedmatch up to a 3,000 match comparison shows quite a lot with me @ around 4 or 5 generations to MRCA.
If we do get a response I'm sure one of us will update for you all