They are unrelated (sort of). As I posted above and in the main thread in post 2, seeds are rare. I'm not sure where you read that bit about the glimmerdust, but it doesn't matter if you're maxed on glimmerdust, it doesn't affect whether you would get seeds to drop. The adventure does drops GD more than anything else though. The point about GD is that if you are maxed out on it, the adventure drops a few more coin to compensate.

If you want to continue, you'll need those 3 seeds in inventory. Good luck!