Created NFS share for testing. Added an authorized IP address for share accessibility. Saved settings. Went to system of the IP I entered for the share, was able to edit the file etc. Tried to access same share on a different system, with different IP entered in NFS Sharing, and I was still able to modify the share.
Upon further investigation, went into Shares->NFS for the share I created and found all values I entered to be missing, including the path to the dataset. See screenshots.
Note: Changes made to Mapall User/Group remained.