Daniel Ryland is the first to respond to the scream. Strides to his front door where he stops as military training kicks in. Listens. Opens door slightly. Recce. Open wider. The cleaning woman, nothing else visible from his own location. Slides around the door, leaving it ajar.
She is shaking, otherwise silent, immobile. Looking down. Not up the stairs. Conclusion: no danger up there, where he can't see.
He locates and identifies a corpse now, but misses the head. Believes he understands the woman's distress.
Poor woman, unused to death. Situation assessed, he assumes control. Prioritises. Then acts.