Don't know about the price, but that certainly seems to be an exceptional bike
Staggering that a bike would be left as-new, unused for such a time. Re the tyres, it's possible. My old road bike was kept in a garage and later under the house, virtually unused for 17 years. Certainly not kept in ideal conditions, but pretty good. When I pulled it out and cleaned it up the tyres were still in excellent condition. One of them was an original from when I first bought the bike, and at that time 26 years old (the bike had been my Audax ride and not ridden a lot at all). I also had two spare tyres - folding tyes, still in their boxes - which were in great, brand new condition. The major killer for tyres and other rubber or plastic components is UV.