How can I add Moderator status in postbit

[Lynne]

From the API:

can_moderate (line 4518) Returns whether or not the given user can perform a specific moderation action in the specified forum
boolean can_moderate ([integer $forumid = 0], [string $do = ''], [integer $userid = -1], [string $usergroupids = ''])

• integer $forumid: Forum ID
• string $do: If you want to check a particular moderation permission, name it here
• integer $userid: User ID
• string $usergroupids: Comma separated list of usergroups to which the user belongs

So, maybe try <if condition="can_moderate(,,$post['userid'])"> Not tested.