Interesting puzzle. I can just "see" the Kiowa VOR on old charts in my mind's eye, but so far I haven't turned up any actual charts.
This website page shows what appears to be an alternate reporting point for IOC, using radials from Denver and Thurman VORs, that might be close. (see upper right-hand corner of page depicted.) Of course, those VORs are probably no longer aligned with the same magnetic variation as from back then. There's the little town of Kiowas in that area, but the VOR may have been miles from there.
https://books.google.com/books?id=w0...vortac&f=false