That's a lame way to make your players pay the price. Lost a The Harbinger Gold Key due to same reason today (random disconnect during the quest...and no it wasn't my internet connection playing jokes). I already had the same problem with advance quests before like 3 or 4 times. Always got a random disconnect in the middle of the quest resulting in a lose of 10-20 advance capsules. They should give players a chance to re-enter a runing quests after a disconnect. Just saying "so make sure you’re ready" is the worsed they could came up with.
Converse with fellow players