Use this command to launch the MSCs as a different user from a non-domain computer. Note, you may have to use the IP address for the server same if your machine doesn’t resolve the name.
runas /netonly /user:abc.domain.com\Username “mmc dsa.msc /server=LogonServerNameOrIP”
I made a simple little .cmd file…with the above command in it, created a shortcut for it, and then set that shortcut to always run as administrator. This makes launching ADUC much easier.