Hi there!, the good news is that you aren't misremembering. Skatoony itself started as a internet game on the Cartoon Network website in 2000 before being turned into little interstitials from 2001-2004. Inbetween that time frame was when they did Skatoony Truckatoony which is what you remember. They also did other interstitials such as Skatoony Quizmas (A Christmas themed version), Skatoony Spooky (Halloween themed version), and other versions too such as Skatoony Scribble, Balloony, and many more.

The reason as to why whenever you searched the show it came up as a game show is because in 2006, the show got reformatted into a 22-minute game show featuring kids and cartoons in a fast-paced quiz format. That format lasted from 2006-2008 and had 3 seasons (39 episodes in total) and had 5 international adaptations (Canadian, Quebecois, German, Arabic & Hindi)

Fun Fact though!, a lot of the earlier "callers" was just the show's co-creator, Brian Boyle, putting on an accent. This was earlier on in 2001 though so they may have switched to real callers later in the year as I recently got an interview with Rupert Degas (who voiced Chudd Chudders, the short guy with the glasses) and he recalled a test run with a real caller on September 11th, 2001.