I don’t work in the team that does that validation testing so I cannot be sure, but I think you would see an email if there’s a specific problem (for player cards). I might not be right about that, we obviously do have a lot of requests to test cards every day as I’m sure you understand.
Otherwise the best thing to do would be to ensure that you’ve followed the details in the testing page I linked to. If the testing works for you but you still fail to get validated, then it is likely that something environmental is preventing us from testing your player (for example, IP block, robots.txt not set up correctly, or a geo restriction on the video we’re trying to test for you).