To throw common sense to one side for a moment
No addition or alteration shall be made until it has been ascertained that etc etc
Ascertained definition - To make certain, definite, and precise.
If he was of a mind.then he could play the awkward part
The situation of the main bonding is not definite
Will testing make it so, maybe,maybe not,it depends on the assessor I suppose
In the day to day job,testing for continuity of the cable to the water pipe would satisfy my addition,but this is an assessment and leaving yourself open to interpretation is a weakness for your application
The reg quoted by Accat gives you a way out
Can you not install another bond in the nearest accessable position