I am just guessing at what the Feds will do. As you probably know, they occasionally go right off the reservation to make stuff up as they go along, as in the case of Bob Hoover. With this one, there will be a strong temptation to make some big CYA moves against the crews, no? You know, a sort of "Hang them all!" move, which the traveling public will simply applaud.
We have already had Mr Babbitt going into a tizz over the fact that someone fell asleep in the middle of the night, as if that were totally unforgivable. In reality, the system did not have anything in place to cope with something that is simply a fact of being human. Trains have "dead man switches" for this very reason; nod off and the train comes to a halt. For a tower, well, perhaps a CCTV link to TRACON, so that they could see why the man went quiet? I am sure someone can come up with some protection for this sort of thing happening.
I think the fairest thing would be an FAA opinion along the lines of "That was okay, sort of, but DON'T DO IT AGAIN!" telling everyone that in future they should divert if there is no reply from the tower for unknown reasons. They can back that up with various ways to figure out what is happening at the airport, of course, but loss of contact with the tower means that a vital safety link is now broken. All it would take is one landing with an un-notified runway obstruction, assuming that it is safe to land without hearing from the tower controller. I cannot see the Feds leaving the tower out of the loop in this way, in future, given the obvious risks.