You don’t safely install from github to dom0 full stop.

If you want to unsafely install the project you mentioned, try following their instructions. If you fail, try to explain as detailed as possible what you did when asking for help.

They’d need permission and even then most attacks would need to be impractical. It’s something to keep in mind but I wouldn’t lose sleep over it.

(app info, mobile data usage, and then set allow network access to off)

If that includes wifi then you’re probably fine. There’s a bunch of other protocols an app might leak data over, such as Bluetooth, NFC, Calls/SMS, USB, etc., but they’re all quite niche compared to a regular internet connection.

I mean the stuff is probably archived somewhere online and possibly already ready to just download or run but that’s no fun and I am also curious.

If you like a challenge you could try to write your own crack. At some point in the installer’s code there must be a condition that goes “If entered serial is correct, jump to installation, otherwise jump to error message.”. On x86 machines a “jump if” is represented by the byte 0x74, whereas “jump if not” is 0x75. In the most simple scenario all you need to do is find the exact byte representing that jump and replace it with its opposite. The installer will then let you proceed if you enter any invalid serial.

At minimum you’d need a disassembler (ideally one that lets you run the installer in some kind of debug mode), and a hex editor. Be warned that my knowledge was very limited back then and has likely deteriorated even more since. Also it can quickly get much more complicated if the installer comes with any form of tamper protection or obfuscation.

If your ISP is blocking them then my guess would be that the local VPN’s ISP has started blocking them as well.

Did it land on its feet?

“Would you like to wake from its slumber the ancient daemon once known by the name of DirectX 9? (recommended)”

OSMC: https://osmc.tv/

Careful though. Google may lock you out of your account at any time, not allowing you to login until you add a phone number.

Maybe the teacher’s just using the software wrong? The “restriction” might as well be a user error. That’s worth considering before giving up and making a Google account, don’t you think?

Ask your teacher to check with the IT department why there’s such a restriction in the first place. Maybe they just falsely assume that Gmail == email? If they actually can’t use any other provider, both you and your teacher should confront the IT department or whoever made that decision.

There’s plenty of older models to pick from https://wiki.lineageos.org/devices and throw LineageOS at.

It sure could make a difference. Another option would be to get an app that lets you choose which apps are allowed internet access, such as NetGuard: https://github.com/M66B/NetGuard

Why do you say Tails isn’t for you? If it’s because it’s inconvenient to use, I doubt you’re going to like Qubes.

If you’re not getting any useful answers, it might be partially on you.

I have tried streamfab and other programs, nothing works.

This will put off many potential helpers because you didn’t specify what exactly you tried or any error messages. Someone who knows a useful program might not bother because you ‘tried other programs’ without specifying. You could motivate much more useful comments by not holding back crucial information.

It’s a nice way of telling you to look elsewhere.

But how am I going to be hyperbombarded with ads during my favourite match of “Who’s The Best At Cheating”? Having to use an offshore DNS resolver just doesn’t feel right.

No they don’t “completely scan your phone”. They’re doing plenty of awful stuff though. Why rely on hearsay and “small hints” if you can be scared based on facts? Here’s a starting point: https://en.wikipedia.org/wiki/Flock_Safety#Controversies

The EFF provides pretty sound advice, see the 2nd link in my initial comment.

One way of helping would be to tell people how to mitigate it. Telling them it’s impossible does the exact opposite.