Cannibal! The Musical Easter Egg - South Park Reference

In the beggining of Cannibal! The Musical, when everyone is in the courtroom for the 1st time after the guy with the grey hair is done telling his gruesome story, you can hear Mr. Garrison's voice say "Ahh Gross" and when Packer's whole party is going into the convenience store you can hear Cartman singing Trey's opening song "Shpadoinkle."