After 2 months I finally got around to doing the /? trick.
I'm posting the results here for anyone that might also want a copy of the command line parameters ...
/forcerefresh will refresh all TVDB, TMDB and TV Maze information
/forceupdate will verify TVDB & TMDB information is up to date
/quickupdate will do a quick update from TVDB, TMDB and TV Maze
/scan will Tell TV Rename to run a full scan
/quickscan will scan shows most likely to need an update:
http://www.tvrename.com/userguide#scan/recentscan will scan recent shows:
http://www.tvrename.com/userguide#scan/doall Tell TV Rename execute all the actions it can.
/export Tell TV Rename do any configured exports.
/quit Tell a running TV Rename session to exit.
/save Tell a running TV Rename session to save its caches.
/hide will hide the UI for all UI elements
/unattended will hide the UI for all blocking UI elements
/recover will load a dialog box that enables the user to recover a prior TVDB.xml or TVRenameSettings.xml file
/userfilepath:BLAH Sets a custom folder path for the settings files.
/createmissing will Create folders if they are missing.
/ignoremissing will Ignore missing folders.
/norenamecheck requests an existing TV Rename session to scan without renaming.
Further information is available at
https://www.tvrename.com/manual/cmd-line/