Well, I'll be go-to-hell. I looked it up and the apple gets the name from a farmer. Here's what Wikipedia says: "Every McIntosh apple has a direct lineage to a single tree discovered in 1811 by John McIntosh on his farm in Dundela, a hamlet near Morrisburg, in Dundas County, Ontario."
There you have it, and I've modified the spelling in the recipe. By the way, for best results when making the dumplings -- use Jonathons. Much better aroma, and firmer, too.