I made a mistake. The DNA testing I had done several yrs. ago WAS through FTNA. I did the 37/37 marker test, but came up with only one "close" relative in the group--James Virgil Alexander. However, in going back 5 generations in JVA's and my paper trails, I didn't see any obvious link between our lines. That was several yrs. ago, and I haven't had any close matches since then.
The only thing I can come up with is that either JVA or I made a mistake in our paper trail. In my case, there's possible mistake in my trail which I can explain in some detail, if you like. However, several other members of the Alexander FTNA group have examined this possible error and believe that my research is correct. That is, that I am a direct descendent of archibald Alexander, b. 1708, Cty. Donegal, Ireland.
I've kept all of my email correspondence with various FTNA group members if that would ever be useful.