So, the issue was resolved amicably earlier today. Apparently, regardless of what has been said here, it is not possible under any circumstances to replace the warranty card. They did not want to swap my watch for a new one, so we agreed the following:
10 year dealer warranty and 20% of any pre owned Omega or Tudor they have available (valid for 6 months).
I was happy to agree to this because I have no immediate plans to sell the watch and may have need of the longer warranty, and because even when I do sell it I think the benefit of the 20% discount will outweigh the cost of not having the warranty card.
I had already seen a watch I wanted, so as soon as we agreed the deal I bought it and saved £1,590 off the sticker price.
this is what I got:
https://www.omegawatches.com/en-us/w...402013001?ab=1
A big thanks for all the helpful advice.