Do we all accept that an EICR is a report on the condition of an installation at the time of the Inspection and Testing?
Can anyone explain why either the water pipe or gas pipe would be used as an electrode, and then bonded?
Is 63Ohms a good or bad reading for an earth electrode?
Does it indicate any instability?
Finally, who believes that the outcome of the Further Investigation would lead to a code C1 or C2?
I see where you're going.
I would argue that the condition of an installation goes beyond just testing though. I could test something with a cracked case and hanging off the wall and still get a pass result. Who knows what state the electrode is in? If it's still even there and/or connected suitably.
And in any case, just because you're called out to issue an EICR doesn't mean that upon arrival you can't identify a problem worth addressing ahead of doing the EICR. It's not all about technically not doing anything wrong, it's about doing the right thing out of care for your customer too.
The outcome of further investigation would likely not result in C1 or 2. I fully expect that if the obstruction was removed the conductor would be revealed, connected soundly to a suitable electrode. But that's not the point. The point is that there is a chance it's not OK, and it's a chance the OP doesn't need to take.