1 : yes F12 a is only when arriving from south , so for me pedestrian can apply too but your solution of living street with motor_vehicle=no is also ok. I have checked the "Règlement complémentaire de la circulation routière" on Anderlecht.be website but text is still before they retract the circulation plan ! 

2) For bollards and emergency : i have spotted a similar one not for from there and they are equiped with DIN 22417 key ; i must go there this weekend i will check if the bollard is equiped or not. 

