interactive video not loading on iPad - EDIT: due to domain restriction?

Hi,

I have created an interactive video using a vimeo video (for test purposes added youtube as well).

Staging Testsite 

It works just fine on desktop and android, but when running it on an iPad OS 16.3 (no matter if Chrome or Safari - sorry can't find the version numbers anywhere on the iPad...) it only states "The Vimeo video could not be loaded."

I have tested vimeo videos by themselves (no h5p, just directly in a wordpress vimeo container) and those work just fine on the iPad. I have also tested "drag & drop" by itself and also that is working fine. So it seems to be the interactive video.

I have found multiple people having similar problems:

https://h5p.org/node/311488
https://h5p.org/node/1284644

but never a solution...

By the way we have vimeo plus, so the links look something like this: https://vimeo.com/123456789. But I do not believe that should be an issue anymore (seemed like an issue in the past), given that we see the video on desktop and android. It seems to be apple specific....

EDIT: I have also included another video, where the setting is "Embed: Where can the video be embedded? - Anwhere" (after reading https://h5p.org/node/1330526), and now the video shows.

Anyone has any idea, what the issue could be, and how to solve it? We do want the domain limit, as the videos are course videos and we want it to be only embedded on our sites.

Thanks!