Is this just randomized? It makes no logical sense and seems unnecessarily confusing:
> The killer took the murder weapon from one of these rooms:
> The gun from the kitchen
> The knife from the living room
> The poison from the bedroom
> The rope from the bathroom
Poison (of the pharmaceutical type) is usually found in bathrooms. Knives are found in kitchens, never near upholstery. Guns are usually found in bedrooms. Living rooms usually have something ropelike. If this is random, it's a bit fantastical, and all of it is suspicious in itself. Maybe limit randomization to shuffling 2 of the weapons around, because some red herrings are expected.
Poison is kind of a crappy weapon for this game if you don't account for it being able to kill without the suspect and victim in the same place at the same time, only them both being in the same place at some point in time.
Also:
There isn't much reason to use the "?" flag on the chart as it stands. Having a witness give vague, "don't remember exactly" or excessively-timeboxed clues ("I was in the bathroom from 9:00 to 12:00, leaving only to drop off some vinyl covers to the living room so I wouldn't shart on them, but don't remember when that was") would add some challenge. The murder solves itself if you just follow the clues, plot the whereabouts of each suspect and look for overlap.