you should be maxed in all factions

That is how it is, mate. You have to be 75 and 100 in reapers, to get the skeleton curse. You have to be Pirate Legend, and 100 to get the Ghost curse.

That... already applies?

For Blessing of Athena's Fortune, you need to have been granted access to the Pirate Legend Hideout (via being a Pirate Legend, none of that "my friend is a PL" type deal) and reached 100 levels of Guardians of Fortune.

For Ritual of the Flame, you are required to have your Reaper's Bones Reputation at 75, and reach 100 levels of Servants of the Flame to then get access to the Reaper's Lair, ergo, the ability to experience and earn the Skeleton Curse.

The only way this might be seen as a problem here, is if your maxed out friend decides to bring you into the lair while you both are already level 100 in Servants, but you are not Reputation 75 in Reaper's Bones.