How to move file from one users account to another? Permission denied.
Its a permissions issue. To resolve simply, first copy the file to /Users/Shared/, then copy again from there, then try to troubleshoot your permissions issues afterwards. You are logged in as administrator, yet you still are lacking the authority to escalate to root or change permissions, and that is odd. Even as admin, you would still need root access to move a file belonging to one user to another users' account. In Terminal, try sudo bash and enter your password when prompted. To use mv command, the syntax is mv /path/to/origin/file /path/to/destination/directory/

Also, changing permissions with chmod doesn't change ownership. You use chown for that.