"Today, the parties announced in a joint statement that Larry will receive $835,000 in exchange for dismissing his complaint. "
They do not mention what their cut of that will be, but since they also do not specifically state they were working pro bono, I'd imagine it'll be around 40-50%.
"Larry will receive" answers your question.
But elsewhere on their website, on the Submit a Case FAQ, they do say very clearly: "Will this cost me anything? No. FIRE is a charitable, non-profit organization and does not charge for any of its services."
https://www.fire.org/research-learn/submit-case-faq