You're right to be following the Fallin (and Fallon) forums since Follin is a common spelling variation on both (as is Fallen).
Other than some rather obvious mispellings, I don't show any clear Follin connections in the Fallin stuff.
But I do have a lead of sorts.There is apparently a "Follin Family" geneology written by one Gabriel Edmonston.Published in Washington D.C. in 1911; Lib. of Congress rev. CS71F668.It apparently lists some descendants of a William Follin who lived near Falls Church VA and died in 1798.
That may be too early for you -- but it illustrates what may be out there.Good luck.