Yeah, I really don't think anyone who has purchased commissioned work or merch in the past has anything to worry about, nor has anyone who has sold said things. Andrew just ain't that kinna guy. Even from here on out, I think it's really up to the artist to get permission, not the person asking for the art, but my knowledge of the legality of these things just is not anywhere near reliable. I read the documents and interpreted it as best as I could, but I'm no expert.
Just try to do what you feel is right and respectful :>