Hi - my name is XXXXX XXXXX I'm an Intellectual Property litigation attorney. Thanks for your question.
Generally, a photographer owns the copyright
except in situations where the images fall into the “work-for-hire” category.
A work-for-hire relationship is created when a photographer is hired to provide photographs for collective works or compilations and signs a written agreement that specifically states that the work is to be considered a work made for hire.
Thus, if you have a written agreement with the photographer, the answer to your question depends on whether or not the contract says that the photographer was entering into a "work-for-hire" relationship. If so, then you own the images and all rights; however, if the contract doesn't say this, then the photographer still has an ownership interest in the intellectual property. IF THE PHOTOGRAPHER DRAFTED THE CONTRACT, it probably doesn't provide that the relationship was a work-for-hire.
HOWEVER, if the agreement says that you are the person/entity that has complete right to authorize publication, then even though the photographer may have retained some copyright to the images, he would still have to get your permission before publishing anything.
Your best option is to have a local attorney read the agreement, and make sure exactly what your rights are, and then you can decide whether to try and compromise, sue or drop it.
But, based on what you've said, it sounds like you should have the sole authority to authorize any publication by anyone - - including the photographer.