RSS for Outlook calendar?

There’s a couple of broad options.

  1. You automate the upload of your CSV file via the CMS API. You’ll need to be comfortable writing PHP code to do that, but it’s certainly possible.
  2. As you suggest, pull the content in to a ticker as RSS, however I think then you’ll loose the ability to filter the events by a date range. It may be possible to extract the raw XML you already have using custom tags - I’m not sure how far that functionality will get you. I suspect for this to work, the XML will need to contain a channel tag which contains items - as an RSS feed would. Here are the links regardless:
    How to extract extra data fields from RSS?
    Ticker RSS Feed extra field namespace how to use?

What you could perhaps do is take your CSV, and with a little PowerShell or similar, convert that to an RSS feed XML structure, which then yes the Ticker module can absolutely show.