I've used this emergency measure to save plants that had root damage from overwatering, rot, cold damage...:

Drill holes in the sides of the pots.
Spray the leaves with wilt-pruf. I've also used a light plastic bag over just the leafy part as a humidity dome.
Give a bit of superthrive in the last watering and then let the soil get pretty dry.

This has worked well for me with Christmas cactus. I hope it has some application in this case!