You need to run this command just before you enter KOTOR 1's final battle for it to have an effect. It will turn Malak into a dancing Twi'Lek at the final battle - an.. alternate ending for sure.
The syntax for the dancedancemalak command is as follows:
Find below working examples of the dancedancemalak command.
This is the only way the dancedancemalak console command can be used.