I have a wonderful instructor once say that when this sort of things occurs during class, in the dojo, you simply must bow to the person.
Bow to them, apologize for wasting their time and ask them to find a training partner who would be more appropriate as they surely are far too good for you to train with. Then walk away and join in with someone else.
The instructor will understand; your new partners will understand; and the 5th kyu Shihan will be standing in their own feces (pardon my vulgarity, I tried cleaning it up).
That's countering arrogance with more arrogance. Works counterproductive in both ways. Just "break" a technique of the "shihan", so he sees that he's not exactly doing it right. Should be enough of a shock to make him stop doing that.