Did you get the homeowner to file a complaint? We have been successful working with the certifying bodies to get people decertified with proper documentation.
I encourage readers to visit the NRPP website to view the guidelines for submitting complaints, which can be found here: https://nrpp.info/filing-a-complaint/
The complaint form explains that NRPP professionals are able to assist the aggrieved party when compiling the details, which I'm guessing could increase the likelihood that the complaint actually gets filed.