Although you haven't used a proper tester to confirm anything, doesn't your test with that long piece of wire prove it is a neutral fault?
I agree with Sunray and John that the best of course of action is to resolve the actual problem, which may well be a bad joint under the floor.
I did ask the other day if there were any connectors blocks behind the light switch (in case by some miracle there is a neutral feed there tucked away)- the video didn't really show us very clearly. I thought I could just about see something that resembled a connector block - but I could be completely wrong about that.
I agree with Sunray and John that the best of course of action is to resolve the actual problem, which may well be a bad joint under the floor.
I did ask the other day if there were any connectors blocks behind the light switch (in case by some miracle there is a neutral feed there tucked away)- the video didn't really show us very clearly. I thought I could just about see something that resembled a connector block - but I could be completely wrong about that.