While I admire people who research to find answers, I am also cautious of creating a theory and then trying to find information that will justify it. There seems to be very little reason to think that Eubie Blake heard what would (in this country and at that time)be an obscure pipe tune.

Blake lived less than 40 miles away from the well known town of Chevy Chase, Maryland. It is important to note that the two tunes have nothing structurally in common.   

It does concern me when someone throws a shadow of doubt on a subject when there is very little evidence or reason to assume there is truth to it. This is how urban legends and falsehoods are created.