My first reaction on seeing the Guardian story this morning was the captain had made a difficult but correct call that the pax were—for the moment—safer inside the (unbreached) plane than evacuating, even if he'd ordered a port-side evac only. Slides always cause injuries, and getting run over by a fire appliance can ruin your whole day. ISTR a captain once saying of a not dissimilar situation, [not verbatim] "I decided the safest place was inside the aircraft, unless the situation changed for the worse". That said, how this captain knew that the situation wasn't about to get drastically and quickly worse I am not sure.
I agree that snap judgements lacking all the data that was available to crew are foolish, and I will follow this one with interest. When what looks like a dodgy decision leads to happy outcome, you always have to consider carefully, I think.
PS Did it really take that long for the fire units to turn up??