I have a wifi dongle I can use with my pi zero W so I stared with a fresh image of the Febuary release of OSMC, added the entry to sources.list as the last line, apt-get update&&apt-get dist-upgrade&&reboot without the external wifi dongle.
Still can not see the built in WIFI after all that. I have uploaded logs to http://paste.osmc.io/jaqesaqogu. Note that I put the wifi dongle back in to upload the logs.