Certainly there were a lot of people who moved from Washington Co., PA to Licking Co., OH. I had ancestors from French, Clark and Evans lines who took that root, all of them originally coming from Elizabethtown, NJ originally. But many other surnames are common to both counties, so I'm sure there were more. My lines settled in the western part of Licking County rather than the eastern part where the McWhorters were, though I've looked a fair amount at Perry Twp., because an aunt of mine married into the Seward family which lived in Perryton. Also there was an Evans family (unrelated) there which I traced down as I was trying to sort out all the Evans of Licking Co., OH.
Anyway, if you make more progress on connecting the various McWhorter lines I'm interested. I try getting the ancestries of everyone who has ever gone under the Dardinger surname and Martha Jane McW... was one so I'd be interested in knowing the rest of that line insofar as it can be discovered. So I'll check your links.