I've never had mine shut off. And I've had it to the angle where the front tires are lifting off the ground going up and on steep enough down hills that the rear tires came off the ground for a minute (didn't know until I saw a video after the fact that it was so close to going end-over). Not sure I could go any further in either direction without actually going end/over. So it is unusual to have it cut out. Haven't flopped it - so I'm not sure on how far sideways it'll go before cutting out or if it would run on its side.
I'm guessing it's the fuel pump running out of supply or something unusual with your setup.
Also - I have had mine go into a limp mode where it cuts the throttle heavily and applies the brakes. When I used to run full rear air suspension if I maxed it out on height and went around a corner too fast it would think I was going to roll over and go crazy. I was just playing around with it when it happened and it caught me by surprise how aggressively it took over. But it didn't turn the engine off. Just shut down the power.