It's Dan Hollandsworth's Vader. It's rather incomplete, but done well enough for this episode it seems.
You know, with a new DBZ series not yet out, and the latest movie only just out recently, it seems kinda odd to have Goku in anything until further information comes out. I thought that was a big deal for them on why they wouldn't touch Naruto or One Piece until they were done with what they were doing currently.
Spoiler: Besides, I got a better idea (click to see content)