In Florida there is a paragraph in the contract that inidcates what is considered closing costs. The verbige could be vague or it could reference prepaid items. Check the paragraphs relating to closing cost, not just the added statement of seller giving the purchaser $10K. This might clear up any confusion.
However perhaps if this was an estate things may have been done differently. You should check with your listing agent and your attorney to find out what kind of seller's concession was given to buyers.
In addition, they normally pad the numbers; they CANNOT have too little money to Close, they MUST Close.
So, they will normally send you a check, a week or two later for your share of the difference.
It could be a couple hundred, it could be more.
Good luck and may God bless