Work Evironment Ethical Quagmire

After serving as the network admin for a small non-profit and general go-to-guy for both software and hardware problems, they have recently hired a new bookkeeper who has demanded and succeeded in removing my access to the network/”his computer”.
I don’t want to do anything to undermine the success of this organization (I’m on the board), but I have a real reluctance to help this new director and new bookkeeper. An added note. I voted with a minority to not hire this individual because he lacked the necessary qualifications and I have spent hours teaching him the software.