PROBLEM SOLVED! (Actually... there never really was a problem.)
Walmart is selling two different turkey fryer set-ups.
One is $37, and includes the burner, 30qt pot, thermometer, and turkey "rack". This one comes with the 12.25"x12.25" frame.
The other fryer set is $49, and includes everything above, plus a steamer basket, smaller (10qt) pot, a little scooping spoon, gigantic hypodermic needle, and has a 13.5"x13.75" frame (it's also got an electric ignition, which kicks ass).
http://www.walmart.com/catalog/product.do?product_id=5155897
That second set is the one I had been looking at on line this whole time, and was the one I was planning to get.
Furthermore, my keggle is NOT 17" in diameter as the internet resources I found had be believing. It is actually 15.75" in diameter.
So... I'm all set. I picked up the fryer today and checked it out with my keggle. I've got a good 2+ inches of clearance at the corners.
I am a happy guy.