You could do this:
Code:
if ( !$postinfo['postid'] OR $postinfo['isdeleted'] OR
(!$postinfo['visible'] AND !can_moderate($threadinfo['forumid'], 'canmoderateposts')) OR
$threadinfo['forumid'] == 20
)
I haven't looked at the code, I'm just going by what you posted.
The above would make it so no one could moderate it at all. If you want to be able to moderate it yourself, you could add this:
Code:
if ( !$postinfo['postid'] OR $postinfo['isdeleted'] OR
(!$postinfo['visible'] AND !can_moderate($threadinfo['forumid'], 'canmoderateposts')) OR
($threadinfo['forumid'] == 20 && $vbulletin->userinfo['userid'] != X)
)
where you'd replace X with your userid.