Need Help With Server-To-Server OAuth App (BuddyBoss Zoom Integration)

We use a BuddyBoss WordPress Website with their build in Zoom Integration. That we can create and provide recordings from Zoom Meetings direct on our platform, we need to build a Server-To-Server OAuth App. Everything is connected correctly but the issue is, that we can’t watch whole recordings. We can start them, but after 5-10 Minutes, there is an 403-forbidden Error visible in the console… several times. In the screenshot you see, after a few seconds more than 130 logs. And this goes on and on, because zoom try to get a connection. See Screenshots

Any necessary informations
BuddyBoss is not able to help us. They say, on theyre end they can’t replicate the issue. Hope anyone has an idea… Do we have make some settings on our server? Maybe place certain IP Adresses on a whitelist.

All I can do, is follow these instructions:

So anything you need to know about the integration and settings is in this video
I did this multiple times… 200% sure to make everything right, but nothing helped.

How To Reproduce
Of course this is a members area. I can’t grant Access. All I have are the screenshots and error messages.

Thank you!