The CD-i games that were released in a jewelcase in USA all have a cardboard jacket originally (in fact, this also counts for the longbox releases from USA, all CD-i releases (that were released by Philips Interactive Media of America) have a slipcase. In Europe, Philips never did this, with a few exeptions, like ac-Panic and World Cup Golf. Zelda's Adventure for example was a Europe-exclusive so it never had a slipcase.
You can check a game where it came from in the copyright section, when it is printed in USA: It's a USA release that originally had a slipcase
Most USA releases by Philips also had a CD-i tag on the sides and on the front like this one (sometimes it was just the CD-i logo, but there's always a CD-i logo on the top left.
[Thanks, Todd MG]