I think the death of these three men will probably go down as misadventure. It was dangerously cold the day of the game -2F but the wind chill factor was making it feel like -24F. It hadn't really snowed that day but Kansas City was dealing with 6 to 8 inches that had previously fallen.
When I look at the obituary image of the guy riding the motorcycle I see a man who isn't really concerned about his physical safety while riding a bike. Probably because he's been doing it for years. I mean, yeah, he knows that you should wear a helmet and probably clothes that protect your body in case of a wipeout so you don't end up looking like ground beef if things go sideways, but here he is riding his bike: no helmet, wearing a short sleeved t-shirt with only one hand on the bars. That tells me a lot about his personality. So if he's not all that concerned with his personal safety while riding a bike, then the possibility is that he didn't dress properly for the weather if he was just going from point A to B, from a car to a house and back. Can't tell about the others.
So lets say all of them are feeling no pain, whether it's from too much booze or a combination of booze and drugs, when it's time to leave after a Chiefs blowout. The homeowner is passed out on the couch, they've never been to the house before or rarely, and mistake the door to the back yard for the front and that's when things go sideways. At first it might be funny falling in the snow but if you're not dressed properly for -24 degrees you are going to be in trouble - fast. Even the neighbours might have heard some laughing and yelling, seeing it as rambunctiousness following a Chiefs win, and ignored it. The homeowner can't hear anything because he's already passed out and within minutes, not hours, these guys are already feeling the effects of the cold. Look at this windchill chart and see how quickly one would be exposed to hypothermia. Minutes not hours.
https://www.weather.gov/media/owlie/wind-chill-brochure.pdf
I presume the autopsy will provide the details of what caused their demise. It's sad all around since three little girls are without a father and other families are grieving a loss.