He will need it if he starts ripping Motorhome apart quote “ sorry sir fridge stated fire the one that you removed again sorry you are not covered on the insurance or warranty , again sorry” guess what £49000 down .Can you give a couple of Elddis dealers a call and ask if they’d experienced issues with the sink? I can’t imagine many people putting up with the problem so if the dealers haven’t heard about issues it may narrow it down to being a blockage rather than a design fault.
Did you see the plumbing when they removed the fridge?
As I said earlier, if I were you I’d collect your vehicle. Leave a letter with the dealer saying something along the lines of you need to store it at home to comply with your insurance t’s&c’s (which is probably true) and that you are taking the matter further, despite removing the vehicle from their premises.
Once home you could do a little bit of investigation yourself - perhaps taking the fridge out, etc. Hopefully your holiday plans won’t be ruined.
Good luck!