They no longer issue lounge passes at MAN - they just tell you to show your Upper Class boarding pass / FC Gold card at the lounge. But as above, the lounge should know it's OK for a UC / Gold pax to guest someone in on the same flight.
Asked at Disney Springs check-in a couple of weeks ago about guesting at MCO (for a trip in 5 weeks time) & they confirmed all is OK. Check in together at UC desk and the other passengers boarding pass will be stamped for both TSA priority lane & Delta Sky Club access.