Even if what Sutter said is true, that the main force of the contact was neck/shoulder, you can still be concussed from that. It's about how the brain jostles within the cranium causing bruising/bleeding. No direct contact is necessary.
If I was Kylington or the team doctors, I'd be looking very closely for any symptoms for the next few days. Taking the game on Tuesday off is just prudent, even if he seems fine right now.