Tom
The ATR is a bit different to most aircraft. The front two exits are type 3 exits, the small type you normally get overwing on bigger aircraft. No slides on an ATR as they are so low to the ground anyway. Yes you would normally expect just the side not on fire to be used but it depends on what the cabin crew saw and how they viewed it at the time. The pax initially did move to the front of the aircraft from these exits. That may well have been the best option rather than hold them up going out of the right hand side or walking back through the aircraft to the main door at the rear and therefore passing the area of the fire. I can’t put my hands on an ATR safety card at the moment and I haven’t been near an ATR for a few years now but I seem to recall that is the correct procedure.
Down the back is a different story. On the right of the aircraft is a very small odd catering/baggage door which is not very suitable to get people out in a hurry.
The only main door with stairs is at the rear and on the left. Therefore if no fire is immediately obvious outside of this door it is very appropriate to use this one as you will evacuate alot of people very quickly via this door. Clearly the crew gave instructions to the pax as they again moved away to the rear of the aircraft initially.
I can’t see clearly on the video but I think there were two cabin crew however there may only have been one, I used to do single crew flights. This makes it very difficult to control everyone.
On any aircraft it normally makes sense to get an able bodied person off first to help other pax and to keep the cabin crew on board as long as possible to aid the evacuation and to try and ensure no one is left behind.
There’s no accounting for the public at incidents like this. From what I can make out the crew and fire department did a good job of getting people out and under control as fast as possible.
Had that ever happened to me I would have been very happy with the outcome as seen on the video.

Cheers – a very comprehensive reply! 🙂