Pure speculation here.
Autoclave (or other piece of equipment that is capable of producing large "belch" of steam) has an exhaust fan/hood over it. (Picture the exhaust fan/hood over a kitchen stove.)
Fan is SUPPOSED to be on when autoclave is on. However, in this case someone turns fan off. Autoclave "belches", perhaps when cycle is finished? and steam sets off alarm. (I don't know about you people, but if I fry anything and forget to turn on the exhaust over the stove, it trips the alarm.)
My question is where this piece of equipment is located. If it's in the basement, the perp might have tripped it intentionally - but if it's upstairs, would an animal tech have had access to that part of the building?
It MIGHT just be a coincidence - if it was, it might have interrupted the perps attempt to clean up/dispose of the body.