Single Player Card Won't Render When All The Others Are


After much trial and error, I have gotten whitelisted for Twitter player cards for all the video tutorials on my website. For some reason that I can’t fathom after comparing HTML between working and non-working cards, one video in particular simply won’t render in the Twitter Card Validator.

Here is the URL:

Can anyone see what the issue is?



I believe we had a high level of traffic to the validator at that time. Your Card appears in the validator for me; can you confirm that you see the same?