After the Seller's columns on a Settlement sheet have been subtotaled, to balance the two debit and credit columns, a credit to the Seller and a debit to the broker would represent:

That the seller owes money.

Explanation:

The debit column represents money that is owed to the seller of the property, while the credit column represents money that the seller owes. If the columns are unbalanced in the manner stated by the question, the seller must pay money to balance the accounts. For example, maybe the seller hasn't paid yet some expenses or fees.