Elaine - I still treat my once sick brug with a dose of H2O2 every so often (once or twice a year). But I also treat it with Epsom Salt (for plants) and time-released fertilizer. It seems to like such treatments. It is still one of my best looking and best blooming brugs. The trunk has a permanent scar from the fungus attack. But like yours, it seems to have healed over.
I, too, thought about planting another one in the ground deeper than 18" deep for the roots. I am really curious to know if that would actually keep it healthy from root-knot nematodes. It's worth experimenting with that theory as I am sure the Brug trees I have in containers would do so much better in the ground with more root room.
If you decide to transplant your pink one in the ground, try shaking off some of the dirt to see if you can view the roots to see if root knot nematodes have attacked it. Here is a good blog site that shows photos and discusses the damage that bad nematodes cause.
http://blog.theplantlady.com/r...
