Luggage Compartment Lights not working

The two lights in the luggage compartment of my 2006 Mk2 Octavia estate are not working.

I have taken them out and tested the bulbs and both are working, so I assumed it is the switch.

However, looking on here I see that the switch is in the tailgate catch mechanism and also operates the "boot lid open" warning on the MaxiDot display.  This display works, which suggests the switch is OK.

It is worth mentioning that the tailgate was replaced after an accident earlier this year, and this may be the first time that I have opened the tailgate in the dark since then so I wonder if the wires have not been reconnected?

Before I start taking things apart, can anyone advise which wires do what, and what I should be looking for?