Yes, it is possible to get you tounge stuck on something cold and metal, and I know from personal experince. One time one of my friends dared me to lick a metal light pole and I did. My tongue got stuck, and it is very hard to get off. It’s not that is stuck really tight, it’s just stuck enough that it hurts too much to pull it off, thats why the kid couldn’t get his tounge unstuck.

Oh yea, I’m not friends with that person ne more.