I used to do classes, papers, and assignments for students, I always accepted the funds through paypal beforehand with proof of work and agreement and never lost a dispute. Only time I haven't accepted money up front is with family, and yeah, you know how that goes.
What you can do, and it's something that is always in your back pocket, is threaten exposure to the school. You have him accepting the deal, you have his name on the papers, and you have a 1:1 copy of the work since most people like that never change anything. I will admit that is very dirty but the pay was really low, and he essentially exploited you.
I mean no offense, I need to see the course work, but $200 for an entire course is a fukking scam.

Bro, I was charging that for a weekend paper. Entire courses are the ~ the price of the class, so 900-1700, depending on the coursework, which is typically detailed in the syllabus or when you login through their portal.