There are many songs that sound alike. Hence the old banjo joke, How can you tell banjo songs apart?
By their names!

I too find that as I start trying to work out a song it invariably leads to another one. I once did that to my banjo teacher. He had gone on a short vacation and on his return asked had I made any progress. "Yes," I told him proudly, "I have figured out at least three songs!" I then proceeded to play "The Great Speckled Bird" which of course is also the tune for "I Didn't Know God Made Honky Tonk Angels" and "It Wasn't God Who Made Honky Tonk Angels"!
Seed, did old Hank really swipe the tuen, or did he maybe change enough to make something else out of an old tune?