Being able to see the engine would make a couple of important differences, especially when it comes to the assessment of the severity of the situation and the following execution of the engine fire checklist with the associated closure of the spar valve and activation of the suppression system would be more prompt. It would also be evident that evacuation were necessary immediately after stopping.
It seems like the whole "slowness" were caused by a lack of cues about the gravity of the situation, which slowed everything down.