Earl is a title, like Duke or Prince.

Just insert a first name for mister Grey. You can find out how he behaves and see if his First Name manifests itself, or if you want to stick with the “grey” theme I can list a few names you might like:

Ash Silver Storm Smokey Steel Shade Alloy Pewter

If you want a less literal grey name, you can always use a traditionally human one. Many languages have names they mean “grey”.