Who is the sales agent of the distinct customer who paid the highest amount in the year 2004?
SELECT DISTINCT T3.lastName, T3.firstName FROM payments AS T1 INNER JOIN customers AS T2 ON T1.customerNumber = T2.customerNumber INNER JOIN employees AS T3 ON T2.salesRepEmployeeNumber = T3.employeeNumber WHERE STRFTIME('%Y', T1.paymentDate) = '2004' ORDER BY T1.amount DESC LIMIT 1