Personally, I’m really very surprised medium chose to censor you! You hadn’t posted even that client’s name! That is a legitimate use of anonymous comment. I know you know that the person has probably made up the story just to get Medium to force you to take it down.
I feel I have to make a state statement there as that is a clear breach of your freedom of expression and speech. This is something central to medium’s ethos. It’s a place to write about people’s own experiences, their own stories, their own lives. What happened to you, especially as clearly as it did, was a legitimate and evidenced behaviour. Instead of sorting it out with you, they went to medium instead. That person had the choice to act professionally, but chose not to. However, they then get medium to censor you is, in my view, an unabridged abuse of power. But I appreciate see people can’t handle the truth about themselves and are so dishonest they’d rather make up lies and stories to get you to take it down. Man you’ve been had and tbh, I am utterly disappointed on reading this news.
However, you want to move past this and I don’t blame you. I respect your decision. The corrupt people who take advantage of those trying to make an honest living are frankly scum. We have the choice to fight the cause, or get repressed by it and may then have to choose to move on. This won’t stop the scum from doing it again to someone else, but there you go. Report back here if Upwork actually do what they say they will. There is a change that having written this, they won’t.
Best of luck!