So. I called the other mom this afternoon right before I took Princess to ballet. Turns out she was calling me about a bullying issue, but not the way I thought! Her son is being bullied and he told her DS is being bullied by the same kid! DS has never mentioned the kid that I can recall.
The mom is very worried that word will get around that her son tattled on the bully and he will retaliate, and that is a 100% valid concern because that's how it usually works.
I called DH and told him what she said. He was going to get DS from band, and I told him to ask DS if he knew this kid and if the kid ever bothered him. I accidentally left my phone in the car when we got to ballet.
After ballet I called DH. Yes, DS knows this kid, and yes, the kid cornered him in the locker room and intimidated him but didn't touch him. Unfortunately DH blabbed the whole story to DS about the other kid (his friend, whose mom doesn't want the story to get around).

At what point did DH become a complete IDIOT? I told him to be DISCREET about it and NOT TELL DS anything. Just ASK him if he knew this kid and if the kid bullied him - no more, no less. DS sucks at keeping secrets, so he was NOT supposed to know the details.
So now DH is mad because I yelled at him for telling DS too much.
DS says he wants me to talk to the principal. DS said he has 3 witnesses who were in the locker room. He also said he told a girl in his science class what happened, and she reported it to a counselor. Supposedly the counselor called the bully in for a chat, but I have no way to verify that.
DS mentioned the other night that he no longer likes the girl he did have a crush on - I have a feeling he likes this girl now. He spent time talking with her at that Halloween party, and now he is sharing things with her that he never told me. Good thing I like her parents, and she seems like a very sweet girl. She also has a black belt in Tae Kwon Do.

She goes to the same studio where Sister and Brother used to go.
So I will be calling the principal tomorrow and telling him I was just informed of this incident. I also want him to tell me why there are no faculty members in the locker room while the boys are changing. That is bullying waiting to happen. DS said he yelled for the coach and that got the bully to back down, but the coach didn't hear him and was nowhere to be found when the bell rang for them to go to the next class.
I told DS if the kid touches him I will file charges through the police, to hell with the school. My concern is that if the kid touches him DS will sustain serious injury.
DS was already in bed when I got home, but I will talk to him more about it in the morning.