I wasn't aware. Probably has something to do with the fact that you either don't know what you're talking about, or don't care if what you say is true.
Trump was allowed to prove the accusation were false. At the first trial. He didn't, and so a jury decided him liable for sexual assault.
After a jury decides something you can't just try to relitigate it in front of another it's akin to double Jeopardy and is called
What is estoppel? What is collateral estoppel? - Ask a Law Librarian .
As to not remembering a year of a traumatic event. It's not uncommon. When I was 12 or 13, about 30 years ago, I was put in the position to have to perform a Heimlich on my Grandmother. I know I was around that age because I remember the school year it happened. Can't tell you if it happened before or after Christmas. I don't know the year my grandfather died just an approximation this because I remember where I was working at the time.
The point is this. Events, even traumatic ones can be both clear, and yet have certain information get lost in time. Including the year it actually happened. Think back at something traumatic that happened around thirty or even twenty years ago and then tell me you're certain about the year?