Doesn't matter though. If ND says its ok, it is ok. If they don't, it isn't. Would like to hear what their answer is. I'm betting they say no, but perhaps they are more enlightened.
If they wanted to encourage fans, they could give a revocable permit (perhaps for a small fee) as a goodwill gesture for the fanbase...with the right to stop you if you start generating product they don't like. But, knowing what I know about them (and about humans in general who are likely busy in their jobs), I will be surprised if they do that. You are probably not worth their time, so they may just say no so they don't have to put up with the nuisance of sending you an agreement. I suppose they could make a scripted oral agreement (perhaps recorded on skype), and just have it apply to only those products you submit as a sample, and limit your volume, above which you would unauthorized without a written agreement...or something like that. But I'm guessing not.