hmm if they gave you prior permission, in my opinion that means you have rights based upon what you got permission for. And as long as you have proof it should be okay. As I feel this kind of notice is usually for people who don't try to ask first, and feel they are entitled to others artwork without respect to the artist.
I actually like to use this one
cause i feel it's more specific .w.
I hope you don't mind my intrusion/comment and hope I provided something useful, if not I apologize.
Good day upon you uwu