Hi @Marks01, the purpose of the video is to use HideMyAppList to Hide GG from the Game as an Alternative to SudoHide, and it works. The idea to Install Magisk is just for that. I can't help you more than this, unless you gave me some Screen-Record of your problem. I'm really sorry, I don't have the idea what's being the problem here. You can use OBS to record your screen.
In reply to your previous question, it's because LSPosed and Shamiko requires newer SDK. You're using LDPlayer 4 with Android 7-5 that has lower SDK (26-24). You need at least Android 9 or newer to able to install.
I'm using LDPlayer 9.0.11.0 x64-bit. I suggest you to install Windows 10 x64-bit to install LDPlayer 64bit. You might want to follow my setup, altho it's not needed, it must be other thing that cause this problem. Again, I request you to do some Screen-Record, so I can inspect the possible causes.