If you have difficulty removing the display from the case, make sure to not just remove the screen. Apparently, if the case has received a knock or the motherboard is sticking to the case, it can be very, very difficult to move the motherboard as well as the screen.
However, the whole screen and motherboard assembly needs to come out. If only the screen moves, chances are the ribbon cable that attaches it to the motherboard may get pulled out of its socket or may even get damaged. I suggest to not use excessive force on the display and be very careful when attempting to pry it open. You need to get a purchase on the whole screen/motherboard unit, not just the screen.
Using a lever through the USB C port and the hole for the headphone jack may help to get the motherboard assembly moving. Be careful, though to not damage theses parts.
I think the guide should be amended to point out the possibility of moving the screen only and its associated dangers.