Ex Owes Me Money And Sent Non-consensual Explicit Video To His Affair Partner

[CA] I have pending venmo transactions, receipts, and some text messages. He soberly bragged to our mutual (who was impartial) about distributing the explicit video to his girl best friend/affair partner. This was given without my consent whatsoever. The mutual friend cut ties with him and is willing to write a witness statement.

In addition, I gave him a deadline of 12/31 written in text before I blocked him. What else can I do to best support my case in small court claims for money collection and emotional distress? Would a cease and desist letter for him and the affair partner be worth it?