Ignoring the fact that the whole betrayal doesn't make any sense, assuming that Hux had had enough and decided to bring the Order down, he'd done it in a way that made sure he'd survive.
I love him, but he's absolutely a selfish man that wouldn't have sacrificed himself for it. In fact, I'd go as far as to say he would never have sacrificed himself for the Order either.
Hux wanted the Order to win, but with him at the top. Sure, he believes in its cause, but imo he wouldn't sacrifice himself for it because he wouldn't benefit from it. Sacrificing others is of course an entirely different story.
That is to say, Hux wouldn't have made some noble sacrifice. The TROS novelisation shows very well that he's a nasty piece of work right until his final breath where his last thoughts are still full of malice and hatred.
And I love him for that. <3