Derived from the wiki: Dyle is the Toon who controls the Gardenview Train Center. He treats everything very seriously and views everything in a professional light, including fellow Toons, whom he perceives as fellow colleagues rather than friends, unlike most of the other Toons. Being raised to supervise the train, Dyle, unlike the other Toons, never participated in the show. This seemed to make him very lonely, which led him to ask Arthur and Delilah if he could be in the show, but this never happened. Dyle might have been isolated from the other Toons, as evidenced by the fact that his room was on a completely isolated floor. Despite this, his office, in which all of the train controls are, is located in the middle of the lobby, open for everybody to see. Dyle was the only Toon who saw the outside world, and the only one who had access to the train that left Gardenview.

 So long as his voice is mature and masculine, do whatever you'd like. Any accent.