So I've been trying to scratch Mr. Stepford off the list but according to a walkthrough he should already be off from something I did fairly early in the investigation (not saying it for spoiler minimizing).

edit: Did I use the wrong guard?

Have you been in the kitchen? Talk to Chef about guard here, then speak to Mr. Stepford about him.

Of course. Sorry if that looks rude but it was among the first things I did at that part of the game. I exhausted the dialogue trees of everyone there for good measure.

No Prob

Now when you went back to Mr. Stepford, did you get dialogue mentioning the broken synth in the kitchen, and does he follow you there to investigate the problem ie, a broken synth is bad for business "Oh My, Yes.."

I even "got him a change of wardrobe".

I wonder if doing all that before attending to any other part of the investigation caused the problem or if I tripped into a different oversight along the way.

The only other thing I can think of is the blond-headed carcass hanging on the hooks moving by the window in the kitchen. clicking on it causes detective to realize crime was committed in kitchen. Oh and the machine in the left side has magnet that causes malfunction. I can't think of anything else