Players idea to Destroy Magic

Ok so in my campaign there is a magical blight that’s basically destroying the land and corrupting creatures similar to delerium from drakkenheim. The players are currently in the Underdark and have found a sussur bark tree in a myconid colony that’s made its home in an ancient destroyed city. The myconids live around the tree as its magic protects them from the arcane constructs and magics of this ancient city but it’s dying and I have them currently helping return water via ancient aqueducts to the colony and tree. One of my players has had the idea that if they could somehow grow a new tree on the surface it could destroy the blight and possibly all magic, I love this idea as a ending to the campaign maybe it grows into something similar to the erdtree like in Elden ring. I was wondering if anyone has any suggestions on how this could be possible as I’m aware of all the limitations the tree has.