I'm no interiors guy but I've got a tear in my roof lining too and I'm planning on fixing it by sticking a patch on the hidden side by pushing it thru the hole and then sticking the flap to it. Will probably use a contact adhesive like EvoStick.
I guess the proper way to do it is to take the lining out but why do it properly when an artful bodge can do the trick?
Don't argue with idiots. They'll drag you down to their level and beat you with experience.
'85 1.6d