Could work well.
What will you do if nobody comes forward?
If never ever anybody will come?
Do you think someone will come up in the end and point: she did it?
No, they will not.
Would you never in the futere give them any supplies? (you said so!)
No, you will not.
After a few weeks you find yourself in a position that you have to come
back and give them supplies again.
That is a lost war.
My suggestion (and I have a long experience with not so clever things I
said) is to be very carefull with what you say.
Never threaten with something that have consequences like the above.
If you say: I will...., the consequence should always be that you can do
and shall do (and should do) what you said.
what are you going todo with the person that comes forward?
I would not come if it was me who made the trash. You could kill me or
blame me in front of all my classmates.
That might be a reason nobody shows up.
What I would do?
I would try to find a way that we could laugh together about what happened.
I would let them know that I have a problem with what I said.
I would find a way to bring a good atmosphere back.
I would always keep in mind my teacher told me: You can't beat them, so
But there lives are maybe more miserable than mine
Or they are spoiled.