Looks like they are not available on Roku anymore as a standalone channel/app.
You can view NAIA from their official Youtube Channel. https://www.youtube.com/@PlayNAIA and https://www.youtube.com/@PlayNAIA/streams (live)
You can either install Youtube on your Roku device, cast to your Roku device, or just run an HDMI cable from a laptop to your TV and bypass Roku altogether.
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From the NAIA website, you can also use the Stretch Internet portal (prestosports) to see the current schedule and watch more live and on-demand events. https://portal.stretchinternet.com/naia/
With the above link, you should be able to cast the content to your Roku device as well or use your laptop and HDMI cable method.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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