Hello Frank Carmona van Kempen
Welcome to Microsoft Q&A!
In this case, yes, you can set a domain as allowed even if it is not listed in the "Websites for video playback redirection" list as the documentation states that those websites are known to work with video playback redirection but that does not mean you cannot use another website. The feature allows you to configure specific domains using Intune or Group Policy, which means you have the flexibility to enable multimedia redirection for any domain you choose, regardless of whether it appears on the official list.
I hope the information provided was useful.
Best regards,
Gao.
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