Not really convinced that these particular wines will keep that long at all. If they were to stand any chance you would have to store them really REALLY well. i.e in a proper cellar or wine storage cabinet. You need to keep both the temperature and humidity constant... a cooler cabinet/fridge wouldn't cut it on the humidity front at all for that length of time I am afraid.
You can certainly try the best you can without splashing out a grand or so on a proper cabinet. Basics would be horozontal storage, cool constant temp and out of direct light.
Mind you, 11 years professional storage of a case or two would actually work out at less than a storage cabinet...
I can't be convinced neither, but it would be a lovely gesture to give them the bottle on their 21sts, they can keep it for as long as they want and there'll always be someone willing to buy it if not to drink but as a keepsake, if they want to sell.