Ratcatcher’s age and the overall Arkham timeline.

In Arkham shadow, ratcatcher is described as being born April 20th, 1988. Assuming that the Arkham origins trailer is correct, that would mean shadow takes place in 2014, making ratcatcher 26. Which doesn't seem right since he looks older and has grey hair. If were to believe the Arkham city plaque that says it was opened in the 20th century, that would make rat catcher like 3 at the time of shadow. When do these games take place??