I have just replaced the damaged wires and re-instated switch as it was. I changed the bulb and checked. All is good. I will need to sort out the wiring in the switch though as that wall is coming down soon and just need a single switch. Looking at it, I think Ill add a spacer to the switch due to not being a very deep back box. This whole thing has been very weird how it all stemmed from a switch in the hallway. Coincidence or not? I do actually have a multimeter but would you believe the fuse in it has blown!