It's still unclear at this point but Batman/Superman #5 seems to make it a little more confusing.
At first RHATO seemed to imply it was still canon but I suppose that can be a little vague. We know that Jason saved Superman's life just not what the details are. In Batman/Superman #5 it seems it might not have happened based on what's said by Batman and Mongul.
Toymaster: You know this guy?
Batman: Only by reputation. He tried to take over the world a few years ago. Didn't work out so well.
Mongul then comments on how he was taken by surprise by the superheroes of the world. There's a little wiggle room if you think about "For the Man that has Everything" and Mongul never officially introducing himself to Batman. When he asks who Mongul is the big guy actually tells Batman that if he doesn't know him already then he can't be important. The dark knight spends most of the story away from him anyway. Technically Mongul was trying to take over the world but he wanted to take down Superman first. Still it might be slightly altered due to the relaunch. It'd seem weird with Pak touching on so much of Loeb's Superman/Batman run but ignoring such an iconic story. Guess we'll see in the annual. Whether it is or isn't I can honesty say it's the book I'm looking forward to the most in January.