Does respawning their tombstones with the Lot Debugger work better?
I've had some varied results doing this. I managed to piss off another two ghosts before I replaced the tombstones - one was hit by a satellite on a dorm lot and brought home by his sister and the other I thought was attached to a different bed so I replaced the one she used. Anyway, I respawned those two tombstones plus the two original pissed off ghosts that I was asking about in the first place. The two original ghosts have yet to make another appearance and nearly a week has gone by in the household so I don't know how to interpret their absence. Their character data still looks fine in SimPE and they still show up on the phone to be rezzed, so maybe they are taking a break from haunting or something. OTOH, the other two have come back out almost every night. I did have to reset their ghost colors on the tombstones because they were both acting like they starved to death (I thought this was an option on the debugger but I couldn't find it in either menu). The one hit by the satellite is still angry about his bed back in the dorm being gone, but the other went to a different bedroom in the house and cheered for the bed in there. Now she's a happy ghost again, so at least I got 1 out of 2 fixed.
ETA: The original two are back on the prowl again and are still pissed about their bed being gone. The one ghost who is happy now is the only one who had slept in several beds in the house so I guess she just reverted to a previous bed to cheer.