Windows Command line Skill assessment

I’mm having issue with this question.
For this level, you must successfully authenticate to the Domain Controller host at via SSH after first authenticating to the target host. This host seems to have several PowerShell modules loaded, and this user’s flag is hidden in one of them.

they have a folder with ssh key in folder called known_host. but i dont know the user name. i tried ssh-keygen to generate public and private key but no help the server freezes on me. what is the username for this and password?