Hello guys, it's been awhile so I thought I should give you all an update.
I actually went to a lawyer to with my concerns about this. He actually gave me free advice initially.
For free, he told me to go down to the courthouse and ask them to print a document saying no criminal record was found, and nicely ask for a signature saying nothing was found. Then write a nice letter to uscis. Well I did go to the court, and like I said no records turned up. I asked the person if they could print it, and I was told because there is no record then there is nothing to print. I then asked if he could print a screenshot and sign it, but he told me they can't do that, signing anything is considered legal matters.
So I went back to the immigration lawyer and paid for his service. $1000.
He instructed me to go to the police station and get all my fingerprints printed. He would send that to the FBI for a background check.
It took about a month for the FBI to respond. They confirmed my fingerprints were checked and did not bring up any criminal records within the federal government.
After that, my lawyer put together an amendment request for uscis. The request included formal amendment to the 129f form, to update certain boxes and that I am now using a lawyer and all communication should go through him.
It also included a very brief summary of what i remember from highschool. It was something like, when I was around 16 years old, I was in an minor alteration with another student, in which I was questioned by police but was never under arrest. I never saw a judge or entered a court room. I did community service. I did not think to add this to my original 129f because it was so minor. But I want to be as honest as possible. Etc.
I have included an FBI background check and a Washington state patrol records check.
My lawyer says they likely will approve, but if they want to dig more because I brought it up they may ask for more records that really don't exist. In which case he said he would help for no extra charge.
Sorry for the late response.