Ok, to summarize again, my PS3 game is from 11/11/11. I played the first half of White Phial maybe 16 months or more ago. Never got the second half of quest. Shrugged it off, forgot about it. One year hiatus. Started up again in Feb, due to DLC. Tonight, when I stopped to drop some loot in my bottomless construction chest at Lakeview, up runs a courier. Very, very rare for a courier outside of a town. He brought me the letter that starts the second half of quest and I now have the filled phial.

So, maybe this will happen to the rest of you who think this quest is broken. Perhaps the alchemist's assistant hires really slow couriers and they take months to find you.