i used the climbing picks to climb up the tower, went to the portal and killed the boss. then went to the other portal to leave and picked up the card along the way. now i got the quest to "awaken the site of power in magwytch marshes" but after i kill the boss i cant pick up the card again.
have you, by chance, tried resetting the realm and entering the site of power again? even if you have the card already, it will go through the motions of lighting up the lasers and everything again.