He didn't so much go himself as made a quick exit so not to deal with the incredible mess he had made. Like throwing up all over a friend's living room and making a dash for it rather than owning up.
There is an argument that the first referendum had one side breaking electoral law and our system being open to misinformation spread by foreign countries. If you have any time for that then I'm not sure how you could want a second referendum until that has been properly investigated and any massive holes in the system closed.