I just can't imagine why they approached this situation in a way that would have to go down like this. At least get a ballistic shield and start to approach him that way. Since it wasn't a real gun, there is ZERO chance it came out as an "Active shooter", because NO shots could have been fired.
Get everyone around him to GTFO and single him out if he is being a little ass and doesn't want to listen to you. Get a ballistic shield wall and approach if you don't have any cover at all.
If you have NO advantage whatsoever...just wait him out from cover until he comes to you.
If you approach someone with a gun, and you don't have the advantage, that exponentially increases the chance you will have to make a choice to discharge a weapon to protect life.
From having airsoft guns pulled on me before, you have no choice to believe they are real. It's a terrible feeling to have thinking "A bullet is going to come out of there, and it's going to split my head apart"
Take your time. Be Patient. No lives are being lost, so use that as an advantage to try and make sure EVERYONE goes home safe