I always remember, years ago, I was working on the east side of midtown Manhattan; I saw two groups of young Japanese business people meeting up with each other. I think some were likely Americans, but of course I can’t be sure.
What I noticed was how they bowed to one another. Of course they did it so naturally, it wasn’t stilted or overly formal at all. And I found it most charming.
I remember thinking: that is such a good idea, it is so respectful, but there’s no touching. More sanitary and no chance some jerk will give you one of those vise grip handshakes (a person like that must be rejected out of hand, pun intended) or, what is almost worse, that you’ll get one of those dead fish treatments (a person like that needs a lesson in handshakes).
I hope your friend enjoys his visit with his future in-laws.
In my Hollywood years I worked for a while at a facility that, among other things, did sound tracks for porno films. I rode the elevator one day with a group of very polite and professionally dressed Japanese business people. They turned out to be the performers who’d been hired to do the “groan overs” on the porno movies. Watching them work was pretty funny... “Hai” hasn’t meant quite the same thing to me ever since.