You should get a couple of those DNA tests done. They will show you if you have any close relatives that have also taken the test, you never know. If your families both came from the same area it’s highly likely that you share at least one common ancestor, if not several. So while he may not have been your brother he might have been your 5th cousin.
I know this because I come from a small rural community and much later in life I was surprise to find out just how many of my high-school classmates I was actually related to in some way but had no idea.