Decades ago there was a frequency guide that listed them as "tactical".
Back in the 80's when OHP only used low band I had a good low band antenna for a while and could hear Lawton and Altus all the time and OKC, Ardmore and Durant a lot of the time. I never heard a peep on 42.60, at least not coming from OK. I heard a lot of other states.
A few years ago Fort Sill was using SINCGARS radios on 42.60 so I don't think Lawton uses it any more, if they ever did.
Two more mystery frequencies are 45.14 and 45.02. Those are licensed but I have never seen them listed anywhere.