Finally got an answer on this. The documentation does say that the API is public and free for everyone, but they changed that policy and haven't updated the documentation.
Hi Dominic,
Thanks for reaching out. As of Feb. 18th, the NFL has secured the APIs and will only grant access to contractual partners. Unfortunately, if you are NOT a NFL Partner you will no longer have access to the feeds or able to obtain access to this feed.
Thanks,
Jonathan Vu
Product Operations Manager
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