Section 3 has to be flown whatever the circumstances. Odd
Aviate - Navigate - Communicate. Since the other two are tested
on an LPC I see nothing odd in requiring navigation to also be tested.
What is odd is that is is not marked M (mandatory) on the Test Schedule.
Also I'm assuming an examiner cannot examine in a variant of the SEP class that he hasn't flown?
An Examiner must have the privileges to be PIC. As long as the Examiner
has any required differeneces training (eg Glass Cockpit) signed off then
they can test in any SEP aeroplane (provided they have an SEP Rating)