I really need to understand the legal process.

For context, my dad had "the knock" everything seized, arrested and bailed. He took an overdose but survived. Forensics found nothing, he says he was out of his mind saying anything (he's terminally ill and had a severe illness at the time) and basically saying he was coerced...

After the NFA letter, I thought ok that's done we don't have to worry about it looming over us - Now to deal with the aftermath and impact on the family.

He then tells me that he went to court in June. Why would he be summoned to court if it's NFA? I said what were the charges, he said there was none.
I just don't understand. I don't believe him, but this process - what's the truth? I've been on public records and found that there was a hearing but nothing else available in the public domain.

Does anyone relate to this?