Regarding the Nintendo Switch. Even though it's a mobile gaming system, you have to be connected a hotspot for it to access online gaming outside of the home. It also doesn't have GPS tracking other than connecting to public hotspots. Otherwise if Gannon played it while out and about he would merely just be playing a game himself & not on the network if not near a hotspot or other wireless. Not leaning toward this because IMO he wasn't in any condition to play a video game that morning. And what purpose would TS have in taking it along? Remember her original story was Gannon ran away, without his phone.
I think it's more likely that he played it in the house online "remotely" with friends other times in the home and they witness that they heard or saw something regarding abuse. When my kids play I can also hear their friend on the other end, so it's possible another parent may have heard something. Maybe it had a Tile attached to it and LS chucked it out along her travels. Calling a Nintendo expert as a witness leads me to believe that they want to access Gannon's gaming account. He may have had a Playstation that he played games on at home & that leads to a ton of possibilities because he could've used it for messaging friends or maybe one of them/parent heard something while playing online with him. They would need access to his Nintendo account for this.
BBM
MOO JMO