Are you retarded? It's a safety no matter what
Then the rule needs to be changed. If everyone holds on the punt and keeps the opposing team from getting to the punter, who is in no hurry to kick the ball out of the end zone, then there is nothing from stopping precious seconds from being drained away.
If everyone is going to hold on a punt like that then, not only should it be a safety, but however many seconds remained on the clock before the snap should be put back on for the free kick.