My usual strategy to force a sneeze over the edge is to look up with my eyes(not at the neck, more effective) and put a flashlight on strobe and it is highly effective.

Another funny human quirk is the clinically proven most effective method to cure hiccups. Especially great if your partner has them and you are willing to help. It doesn’t matter how the stimulation happens either, but they were more appropriate with their testing methodology than a couple needs to be.