Please, Don't misinunderstand what i am saying.
I do not advocate telling the cabin crew which exits to use/not use, without expecting them to use their own judgement.
By saying 'evacuate', the cabin crew should and will use their own observations to evaluate whether that door is viable.
By saying 'evacuate, caution, (fire, something) on the left' the cabin crew should still be using their own observation, and deciding accordingly. However, the reminder is there that there is a fire on the right, and the flight deck may have some information not immediately apparent/visible from the cabin crew stations. All that has been done is to point out a potential hazard.
Post incident/accident, we should all be following the training. But in most cases, it will be the first such situation experienced for real. And so peoples reactions and responses will probably vary quite considerably.
I would certainly look to keep things as simple as possible. At the same time, providing any useful support and information as I think would help everyone.