if {Meddling Mage} went to the graveyard or was unsummoned or was put on top of library etc will the named card still can't be played?
I wanna say no because it's not on the field but I know there are some cards which still can interfere with the game ever after death.
Once it dies the named card can be cast again. I don't know the exact ruling for that, but I'm almost positive that's correct.
Meddling mage's ability is only active when she's on the battlefield.
Permanents would have to specifically say otherwise if the card would continue to work in any zone other than the battlefield.