Blades Electrical

Yes
the house would benefit from having and eicr (electrical installation condition report)
this would test all cables and fixtures to allow to give a good report on what i would advise to do next.

Ur supplier would not replace this as anything after the cut out(main fuse) or meter belongs to the home owner

This could be patched with more plasterboard.
and sealed with iridescent (fire resistant sealant)
but to also allow the fuse board cover to be removed and maintained .

If he was to turn up at the door please say no you aren't paying as they didn't fulfill there side of the verbal contract and didn't call before ur arranged time to suit ur time scales

The new fuse board would be upgraded with an rcd/rcbo which is more sensitive to earth leakage and it picks up older appliances that may be faulty