Couple of things..
What does Stalhrim have to do with the Game of Thrones?
Also, use paragraphs. I'm sorry but I had troubles understanding what you said, paragraphs might help making your text appear clearer (not trolling, this is a friendly advice since my english used to be very poor as well, and it's still not even close to great, so I feel you

).
From what I understood, you're gonna make Stalhrim weapons for your mod, and you're trying to decide whether you should release them as a resource and demand that we reference to your mod or if you should make the weapons unique to Issgard?
Personally, I think that demanding to reference will turn a good portion of people away from using the weapons (I myself wouldn't mind it, I'd just call them Issgardian Longblade etc, but would probably try to agree on something good with you for the best idea) but it's indeed a good way to promote your mod.
Alternatively you could make them unique to your mod only until you release the mod completely finished. A lot of people do that, Morrowind modders mostly always release their mods with permission that once the mod is released in it's final version everything from it becomes a resource. You could name them all related to Issgard or some more specific place of your mod (but Issgard is probably better since the mod is called Issgard) in your mod already, and simply request that their names are never changed when used in personal projects.
3rd remember to make a good story. IIrc Stalhrim in Bloodmoon was never said to be unique to Solstheim so I'm not too sure why isn't it there in Skyrim, but if you find a good explanation it might be a great side story with a small questline or something. In any case at least make a book about it, don't just stick it in few random caves and around a smith or two without explaining anything. Just a suggestion.

If I'm wrong and it is unique to Solstheim someone definitely correct me.
Hope this somewhat helped.
