The obvious converse of evolution by mutation followed by natural selection is that an absence of mutation will result in no selection.
True, and yet there is protein expression in humans.
By all means cite evidence of expression of a heavily methylated retroviral insertion.
I don't know about your qualification of "heavily methylated", but generally regarding trancriptionally active ERV's and protein expression in humans, as well as possible functionality, and interestingly, even insertion bias - Perpetually mobile footprints of ancient infections in human genome - Eugene D. Sverdlov
Cordially,