Check that the cane is still stable in the soil, this is a good indicator that the roots are still viable, if it is extremely wobbly the root system may be damaged beyond repair and there is not much hope for rehab, if the cane is stable take the following steps. Dump any standing water that may be in the plants liner. Place the plant in a spot where it receives diffused sunlight for as much of the day as possible. Allow the soil media to dry completely before attempting to water again. Use water that has not been softened when attempting to water again.
Best case scenario the cane will begin to produce new foliar heads overtime. Remember that Compacta is a very slow growing plant, so it may take quite a while to refoliate if it is going to do so.