Or have it set to auto, like most cameras. Especially as it's unlikely he would know the settings in advance or that it would happen.
photographers don't tend to set their cameras to auto
he'll perhaps use aperture priority or shutter priority, he'll likely have chosen the lens, set the ISO and chosen either the aperture setting or shutter speed for that environment... any of that is perhaps more important than pressing the shutter.
though granted he's got no control over composition