It would be inappropriate if I was some nobody who wasn't even in the RP, just coming in to advertise my own creation. As the Co-GM, I've put quite a bit into this RP myself, and I know destiny as a personal friend. Destiny knows I have no ulterior motive behind being here, and there's no better way to have a small group RP among friends than to let my friends, including her, know that it exists.

In fact, it is no different than you advertising your stream in the RP. Just as I could have shown my RP through PMs, you could have done the same with your link.