Your in the right hand seat - because your club requires it - then you log it as PIC and isntruction given, they log it as dual.
Case G - Section A Page 44
LASORS 2008 | Personnel Licensing | Safety Regulation - very clear if you ask me.
In my eyes there is no other way to log it legally.
I am responsible for the aircraft not them - or as stated I am a passenger and cannot log anything.
I know which way everyone logs it at two schools I worked at.