3D FlipBook - Certain videos will not play

I have a number of videos that I am trying to add into my PDF book. I have found that only some of the videos will actually play. These are the videos:

WILL NOT PLAY: https://www.youtube.com/watch?v=nqpNv_TUu0Y&t=135s (ID="nqpNv_TUu0Y") https://www.youtube.com/watch?v=pQaUimEjzdA&t=630s (ID="pQaUimEjzdA") https://www.youtube.com/watch?v=nswrzcciZww&t=7s (ID="nswrzcciZww")

WILL PLAY: https://www.youtube.com/watch?v=Mla9YptlvxM (ID="Mla9YptlvxM") https://www.youtube.com/watch?v=1RCVzCmOHFI&t=83s (ID="1RCVzCmOHFI")

Could you please tell me why the 3 at the top will not play. Have I got the correct video ID for these videos? There is no problem with my HTML or CSS as I have been able to SUCCESSFULLY play 2 videos.

Any help will be most appreciated. Thank you.