What are the rules for the domain admin password?
We are having an issue with "$" and need to escape it with "\" to get it to work.
Storing a password that contains a $ sign in a configuration file shouldn't be a problem.
However, there are shell restrictions and behaviors (depending on your shell) that may cause issues due to different characters interpreted in different ways.
Since "$" is used by several shells as a variable, you had to escape it with "\".
When running the command, i.e. with --password via the command line, make sure to put single ' around your password (i.e. --password 'pa$$word').
Some additional information can be found here.