"_XSERVTransMakeAllCOTSServerListeners: server already running"
suggests the system (user: gdm, uid: 116) display manager X server on VT7 owns/uses the socket in "/tmp/.X11-unix/" which prevents the user (uid:1000) display manager on VT2 from using the same socket.
The report in /var/log/ Xorg.0. log:
"_XSERVTransMak eAllCOTSServerL isteners: server already running"
suggests the system (user: gdm, uid: 116) display manager X server on VT7 owns/uses the socket in "/tmp/.X11-unix/" which prevents the user (uid:1000) display manager on VT2 from using the same socket.