Right there on the floor. The solution. He stalked slowly towards it as though it would run away. "Blondie, come here," he said. "I think I have the answer."
Curious, Andrea got up and followed him to the door. "The answer to what?"
"The answer," he said, scooping up the rubber doorstop and showing it proudly next to the photo on her phone, "to the stuck door."
It was the right kind of shape to have made those marks. "So you think the door was wedged to stop you from finding the body early?"
"Right," enthused Kyle. "That door stuck sometimes, but a ploy like this would never leave it to chance that I might wander into the room at the wrong time. They chocked the door to make sure I couldn't get in. Here!" He handed her the doorstop and stepped outside, pulling the door closed. "Go ahead!"
He gave her time to put the doorstop in place before testing it.
"Firmer than that," Kyle instructed, "really get it in there."