Even if you had the password the likelihood of it being corrupted is high since you copied it while it was running! 
Anyway that's irrelevant because without the forgotten password that copied VM is nothing more then wasted space on the disk and might as well be deleted because there is no practical way to retrieve the password! 
If you still have the VM running on the other Host then I'd make sure that you, from within the running Guest OS, backup off of the Guest OSes Filesystem any User Data that you do not want to loose. Once you're sure you have all User Data and Settings as might be required backed up then it's time to create a new VM.