I think Juan Brown (blancolirio) gives his usual in-depth description of the accident. Lots of ATC recording gets played. He is always careful to state what is "preliminary" or "assumed". At one point, it does sound like a different controller is on the frequency also.

As he states, it's not uncommon to reduce staffing at some airports during late night hours due to normal lower traffic activity. However this situation @ LGA was magnified by United aircraft on the ground experiencing odor (smoke?) problems with pax on board while sitting on taxiway waiting for a gate to unload pax. That was the reason for the fire trucks movement.

Watch/listen to his YouTube assessment#mce_temp_url#. I'm sure he'll have follow-ups in days to come. He always does.