Yeah, 了慧 should be correct. Here's her profile on the site of a gagaku group she's part of:
http://www.mahora-japan.com/htmls/profiles2.html (first row).
了恵 appears in conjunction with Kirby's Block Ball, but
the credits from the Japanese version are in English too, just with the name order reversed, so I'm not sure if that variation really comes from a game or not.