I agree right engine runs for about a minute after the aircraft comes to a stop, fanning the flames. Apparently did not deter pax from evacuating (good thing). I have no idea if that was simply how long it took the crew to "unstartle" and run the shut-down list, or if the previous impact and/or hypothetical lightning strike had damaged engine controls (remember "stuck" #1 engine on the Singapore/Qantas A380?) It may simply have stopped only once the fuel had leaked out and burned on the ground.
Salute to whoever it was that ran back into the burning plane. I suspect it was the FO getting the CAPT out of the cockpit and down the slide head-first (dark "objects" on slide). Zero further comment on crew until we know a lot more about what degraded controls they may have been fighting.
Agree the fire response was slowish - but we don't know what they were told to expect and how they were deployed. Remember there were comm problems with the aircraft.
Whatever else goes on with the SSJ-100, it looks like it may have a "Ford Pinto problem." Tendency to collapse gear in a way that ruptures fuel tanks.