You will have to pay for any re-take of the exam. Is that the answer you were looking for? I am not completely sure what you are asking, can you clarify?
From the Cloudera Certification page:
"Candidates who fail an exam must wait a period of thirty calendar days, beginning the day after the failed attempt, before they may retake the same exam. You may take the exam as many times as you want until you pass, however, you must pay for each attempt; Cloudera offers no discounts for retake exams. Retakes are not allowed after the successful completion of a test."