Hope they didn't go on the Scenic Railway ride. The link you provided said a girl was killed on it the first day it opened.
I read some of the pages on the site, but not everything and not the page about the scenic railway, how terrible. I read it today. I also need to be more methodical in my scanning/note-taking combination as I found that the unknown location for the miniature railway was actually written on the back of the photo, and it's at Rhyl (North Wales). I think it's the same little boy, I checked at Belle Vue in case it was that railway, and there is an RMR engine there, but then dug out the photo and found the answer was there all the time.