A group member unlocked the dirge, Rosa Dod. I can't see or target the mercenary. If I cure her, it says I cured X from 'Unknown'. This persisted through zoning, relogging, etc.
I bugged this yesterday. None of the group I was in could see Rosa even though she showed up in the group list. No problem with other BoL mercenaries so far.
There's an intermittent bug in which some members of a group or raid cannot see some or all of the other members. One fix is to go to EQ2 Button >> Options >> Alternate Models, then turn them all ON (or OFF, if you have them on to start with). Save the change, then go back in and set it to the way you had it to start with. Another is to try camping to yourself (i.e., I might use /cam Sigrdrifa). Do either of those things help?