The loud crash woke Ben, his first instinct was to pull Fitz against his chest and protect his lover from whatever danger was upon them. When he realized that they personally weren't in trouble he let go and got up, pulling his long coat around himself before venturing outside where they witnessed Kristoph suddenly erupt into flames.
This fire was different and one he couldn't control but when Abby asked him for help he followed without hesitation. The pile of ashes was still very hot but he picked up something he could clearly see among them and followed Abby to the management wagon.