Currently there are no OFFICIAL Dynamics NAV Exams. Microsoft no longer have specific requirements to their partners, that their employees are “certified” within Dynamics NAV.
Dynamics Pro is an organization under Dynamics Communities, Inc. (the company also behind NAVUG, AXUG etc.). So while most of the exams have been developed with the volunteered help of some of my NAV MVP colleges, as a contribution to the NAV community, then they still have to make a profit, now that Microsoft no longer pays most of it. Like any other company.
So it really depends on WHY you need a NAV exam/certification? If it’s in the order to get a job at a partner, then you should first ask that partner what they would look at when hiring a new employee? If this or there exams. is what they look for, then it may be worth the money. If they don’t care, but rather want to look at your experience and previous work, then no exams. will help you.