Hold the phone!
I called Kodak Head Office on 01442 261122 and they were familiar with the issue and put me through to a very helpful chap called Chris Mayo at Kodak Ltd, Boundary Way, Hemel hempstead, HP2 7YU (01442 846674). They have all the negatives from Elegante Wedding Photography and for a £25 admin fee, they will retrieve the negatives from their massive archive and sign them over to me so I can have my own prints produced from my own lab whenever I want!
Fantastic and very unexpected news. I thought I'd post this for anyone else who seeks their old negatives if they were photographed by that particular Kodak franchise.