I would expect much more heat and flame damage than seems visible in the photos.
I agree...
The discolouration on the right hand fuselage side may even be from the MDC initiator cartridge.
Was the MDC initiated? Have to wait for the report(s), etc. Discolouration from MDC initiation would be evident around the canopy frame, would it not? The discolouration evident in the image "appears" to be from the Rocket Pack efflux. Is the discolouration evident in images showing the other side of the aircraft?