Billy,
I think it is safe to assume that if there is a policy that outlaws such a situation, then it is very possible that there would be all kinds of ways to make sure that does not happen. Just like you do not play the game without a safe environment, if the rule/policy says to not play the game with only one official, then you do not play with one official. It seems simple to me.
I have also worked many games by myself. Many times I have worked by myself because someone did not show up or there was a complete mistake on the person assigning the game. In my cases it was the AD usually did not give the proper information. No shows from an assignor I have not yet experienced.
That being said, when I have worked by myself in a game, I did not follow any set standards or tried to. I understand that this is not the ideal situation, so I do not really care what procedures others follow. I just try to get in the best places to call the play that is in front of me. And that is why many places probably have no written mechanics in the first place. If you want to have them, I likely would not follow them. I just think you cannot put all officials into a perfect box with this kind of situation.
Peace