Boyd I think your analysis is on target. Yes, Morris C was one of the four (can't remember the fourth, maybe a non-broadcaster silent partner). Hoisington was first and foremost an engineer - was a broadcast equipment salesman at one time, and later built and operated stations in Andalusia AL and Milton FL.
I remember hearing this post-game analysis: someone came to the stark realization that in 1973 a Vicksburg-based independent FM could not generate enough revenue to sustain three executive salaries, so one by one, they left. In retrospect, this is obvious.
(I posted this comment earlier, but it did not seem to take, so apologies if it is duplicated)