I want to make sure that entries in the exports file are only commented out not removed:
Here is the man page from exportfs:
Unexports a file system path and removes its export entry from the /etc/exports file. Use the -z option to remove a file system path from the /etc/exports file without manually editing the /etc/exports file. Note: By default entries are actually commented out and not removed from the /etc/exports file. To change the behavior to actually remove entries switch off the nfs.export.exportfs_comment_on_delete option. For more information see na_options(1).