Your post had me thinking...and I'm by no means an expert on this history but it's questions like yours that get many of us thinking and reading and speculating and, whether any of the conjectures prove to be right or wrong, we still manage to learn a lot.

Initially it occurred to me that these might be some of the families that went to Ulster in the Plantation (my ancestors among them) but a little thought led me to the conclusion that that wouldn't be the case. Most, if not all, of the Scots who were "planted" were Lowlanders and the main "plantings" were done in the early 17th Century. Seems like these folks bringing any tartan with them is way unlikely. The whole Coats Of Arms thing is a can of worms that comes up often on the forum...search the forum for some of the threads on that topic.

Sorry that I can't contribute anything helpful to your query but remember that while you may not be able to prove it correct, finding out that it isn't correct would be as important a history lesson as proving it is.

Best

AA