He's definitely as old as Thompson at least. Lots of these guys lie about their age. I remember Glen Johnson about 10 years ago they were claiming him to be 37, but he was clearly older than that. He's probably 55 now, and he's still fighting. Like the OP said, it's often their amateur coaches and national teams who start if off, to get them in junior championships when they are over-age. Other times they just lie when they turn professional because it's easier to get licensed. Boxing commissions worry about licensing guys in their 30s and 40s.
In football that has a particular reason. I don't see the benefits of it in boxing at all. He just looks old. People usually think me older than I am too. Some people are just not lucky.
So supposedly Ruiz is some mid 40s Cuban who outperfomed former Ring Champ Wlad against their only common opponent by a landslide. Makes perfect sense.
I'd like to see Ortiz in better shape, as he looks too fat. Fury would UD him by keeping the fight at distance and being better conditioned.
Case in point, Adonis, Adonis is another older guy and does not look anywhere near as old as Ortiz. I think there are some numbers juggling regarding his age.
Some people just look old. Greg Oden, former NBA player, was 18 when this photo was taken. He looks like he's pushing 40. http://i.kinja-img.com/gawker-media/image/upload/axqnc9uoh8hxocilupgu.jpg