Finally! The BigY test is complete!
Here is the group of men whose trees it looks like I need to focus on and build out their trees. The connection is likely in this group.
When I look at the block tree, there is only one other match in this group.
If I am unable to find our connection in the above group, I may need to go up one more mutation and build a larger tree down to find our branch. I’m hoping I don’t need to go that far back because that will take forever to find the answer.