I don't know if it has been permanently fixed or if the bug was bugged. But when I took the mage back down to STV to clear a few grey and green quests I popped over to see if Galvan, Gavlan, Gevlon, Gablan, whoever-the-fuck had been fixed.
First off I had to go all the way to BB and abandon the quest and retake to get a new knife. I must have dumped it when I had full bags or something.
So back up to the Rebel Camp and a little running and I swam down to his little Altar of the Tides in the Cursed Reef. I didn't even have to use the knife. He was already there and hostile. As opposed to un-summonable or friendly.
I don't know if they have changed him so he is always there and always hostile, the quest has been fixed or a GM had been coerced into resetting him for someone. I don't care. He was red then he was dead. Tada!
I had put in many tickets concerning him and persuading GMs that they could reset him. If they accepted that they could do they would tell me it had been done and close the ticket before I could find that they had done bugger all and he was still bugged.
Whatever, quest finished.
Next up he went to try and solo Negolash. Maybe a frost spec would have been better. A Repair, 5 BBQ Buzzard wings later and a quick visit from EvilBastard and he's dead too.