Needed help with understanding how to download DRM protected videos

Hey so like I have subscribed to a course and the issue is its about to end in a month or so and I have not yet completed it. So I wanted to download these videos so that I can complete it later on.

But these videos are all DRM protected. I have looked through some of the ways to understand what it is doing and handling and figured about using TamperMonkey to get the PSSH Keys and from there also figured that it uses Widevine DRM (or so as the image attached suggests)

though I looked around and most of the forums were telling about mpd keys which i can get from the network tabs but there is none of them here.

Some more information

– The website streams audio and video separately, its using requests like 206 partial content to get these

– There is a license request that happens before the video I think to verify if the user is subscribed or not

You can look what it is doing mostly in these screenshots