you are already using xinerama/twinview..
the logfile does enable Randr, but the driver apparently can't use it
with twinview.
** Package changed: xorg (Ubuntu) => nvidia-graphics-drivers-180
(Ubuntu)
** Changed in: nvidia-graphics-drivers-180 (Ubuntu)
Status: New => Invalid
--
RANDR ex
** Attachment added: "Dependencies.txt"
http://launchpadlibrarian.net/28843809/Dependencies.txt
** Attachment added: "LsHal.txt"
http://launchpadlibrarian.net/28843810/LsHal.txt
** Attachment added: "LsMod.txt"
http://launchpadlibrarian.net/28843811/LsMod.txt
** Attachment added: "LsPc