It's 2-rail O scale. If you google "heaton lodge junction model railway" you'll find a number of links and videos, including https://www.britainsbiggestmod....com/index.php#About. Considering that it's O scale, described as having 3 miles of track, fully automatic operation, etc., along with the fact that custom layouts can easily run into 6 figures (I assume not including the trains), the stated number doesn't sound impossible. If that's how he wants to spend his money, so be it.
The article can play up the relationship angle in order to capture eyeballs, but I'll bet he has plenty of money left to spend on her.
