Hey Chris,
Thank you for reaching out to us!
The Other URL option only allows you to import Events that are published on another website using The Events Calendar: that’s the reason why your imports are failing for CSV URLs.
We already have a Feature Request to import CSV files from any URL here:
https://tribe.uservoice.com/forums/195723-feature-ideas/suggestions/31789591-ability-to-perform-a-csv-import-from-any-url
I would recommend adding your vote there. This allows us to gauge interest in this particular feature request, which helps us prioritize our development efforts.
In the meantime, here’s a tip that might come in handy while this functionality does not exist natively:
We’ve heard of some users having success with WP All Import (or similar plugins). These links may be helpful if you want to try going this route:
– http://www.wpallimport.com/tour/scheduled-imports/
– http://www.wpallimport.com/documentation/custom-fields/theme-plugin-fields/
I hope this helps! Let me know if you have any other questions and I’ll be happy to assist!
Best Regards,
Patricia