My mom was/is a master at bringing the dead plants back to life.
She always said , not to much water.
I dont know what growing medium is good for a dragon tree but I would say as posted above get rid of any standing water. Let it dry out and water lightly
I dont know anything about dragon tree plants but might want to get some purified water, tap water can have to many chemicals. Like Chlorine
If it has signs of life , give it time.
Make sure it gets the right light and temps. It took 4 months for my Ochid to even show signs it would come back and a year to fully recover and send out a bloom stem