TiredSoul

Interesting question with a tricky answer.
I think the FAA council has several rulings.
There was one accident investigation of two MEI’s flying together and both logging ME PIC time. One as dual given.
The FAA found them fraudulent as there was no instruction taking place or at least not logged.
With 5000hrs I think you have a hard time proving instruction took place.
Unless you are providing a service such as conducting a Flight review, IPC or a Wings Program flight.
In any case sign his logbook for dual given and what instruction took place.
Make sure his logbook matches yours.
Keep in mind that an incident can occur completely outside of your control. Like a nail on the runway, flat tire and off into the weeds you go.
Who was PIC, who are you, what were you doing in that seat?
The FAA will want to know and so would the insurance company.
Owners can turn on a dime if their toy gets destroyed. And all of a sudden you’re on the hook as you’re the one with the highest rating.
For exactly this reason I would always take the RH seat even as a passenger.
No way I’m getting caught in the backseat during an incident and not being in a position to affect the outcome.
It’s really not worth to risk your career for a handful of hours of “dual given” wink wink....