Yes, I realised that was an issue that some might raise but, as I said, provided the switch was definitely (and 'reliably') break-before-make, I don't really see a problem - I'm sure that the insulating material between the two contacts/terminals, per se, would be more than able to cope with 400V between them.
That's the problem in the orange circle, the 'permanent live' and 'switched live' should not be connected in the block together. I'll guess the brown is permanent however I can't be certain, the damaged blue requires repair in some way.
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