Didn’t we get a mini story arc like that recently? Something about Adam going back to the coffee shop after a big job and discovering that Andre had laid-off most the staff and could barely afford to pay the utility bills?
I wouldn’t say a Murder Mystery has to have a murderer, Natural Causes/Suicide is a valid story Climax. The problem is, its harder to make a reveal like that without making your audience feel like you wasted their time after spending so much time with the other “suspects”.
Why not both?