Clarification on EJ for firestopping Seismic Joint

Hello. I received an EJ from your engineering team (attached) for firestopping a 6" wide seismic joint. The EJ shows a firestop joint spray overlapping or lapping up concrete surfaces, but the note says the joint spray should overlap "adjacent" surfaces. The construction joint terminates at the edge of the building and there is an unknown accordion rubber/fabric material which runs vertically up the entire building. We don't have any specifications on this existing material. Could you verify that we can terminate the mineral wool safing at this accordion fabric and lap up the hilti firestop joint spray onto this fabric? See attached for a copy of the EJ we received from your team and some images/plans of the condition.