Lawsuit on past commission

@sjrcpa   Why would you assume that lawyers do contract cases on a contingency basis?  Yes, some of them do, but often when it has already gone to judgment and it's just collection work.  Enforcing a contract is not like paying chiropractors for whiplash.  Businesses, unlike bad drivers, don't have insurance policies to pay contract debts.  Lawyers know that contract judgments can be discharged in bankruptcy, so that even if you win it's uncertain whether you will collect.  

I wonder what is meant by "we had to file a suit."  Maybe there were twenty people in the same situation, not really enough for a class action, but they each chipped in $1,000 and that was enough to convince the defendant to settle because otherwise the contract might have said that the winner had to pay the loser's fees.  That fee should have been deducted in the year paid. 

Even if just one plaintiff is involved, there's not enough information here to know what expenses were paid, or in what year.  To answer the question: No, this doesn't sound unique, it sounds run of the mill, and you can't "take a percentage off for expenses."

“Defer to our account(ant?)”

IRS would probably argue that the interest is subject to SE tax if the underlying claim involved SE income. It’s an “interest”ing topic.

You really need more details about what this claim involves. Just a guess, was the $51,289 for legal fees paid before the case was settled?