Better to ask for forgiveness rather than permission. @HoughMade has it right - they have now already been informed, and if they disregard - could end up in hot water.

Better to not ask permission. Just show up, be asked to leave, (Get photos/videos of being asked to leave), and then continue protest peacefully in the sidewalk since they kicked you out.

Disregarding a formal request loses you the ability to claim ignorance unfortunately