You can only take a guest if you are a Platinum and they are flying Etihad, doesn't matter where to or with you etc (have often offered bedraggled souls a chance to unwind and shower etc whom I walked past in the airport - real mixed bag of thank you and ... is this place !)

Just flying F doesn't elicit any favours for other PAX though you can get access for them for $100 then get the Residence room for another $100 if you like and chill out !