If you just want the brackets gone:

What you could do is export the object into Hexagon and assign a new material to the brackets only. (If they don't have that already)

BUT DO NOT DELETE THEM OR CHANGE THE OBJECT OTHERWISE!

Then create a new cr2 with that "new" object.

Then you can simply make the brackets invisible in the material room by making their material 100% transparent.

The original morphs should still work then, as you didn't changed the object itself.