My first thought for Zac is Kaiji Tang, the voice of Ichiban Kasuga from Like a Dragon (also voices Gojo in the English dub of Jujutsu Kaisen), mostly because his Ichiban is pretty much how I envision Zac (goofy, kind of a dumbass, heart of gold lol), but I think it might sound too old for him lol

[youtube]https://www.youtube.com/watch?v=3UJBr2zj5pU[/youtube]