You don't see anything special in a scenario where the three options concerning the deal are: No deal, deal or no Brexit?
The options aren't even balanced, they are heavily stacked in favour of no Brexit and I would like to read the question actually asked because I don't see one that would lead to that set of answers. So if the MPs decide to organize a referendum on the deal, it should be about the deal and only the deal; if they believe that the first referendum isn't right then they virtually answered the question themselves and should just do their job instead of dumping it on the voters.
Though there is a third option, if they believe that the voters have been cheated and based their votes on falsehoods then repeating the first referendum would be justified, imo.