How did you want to handle quest reloads? Did you want to make the player's quest reset to the new quest specs? I could see a problem if a quest step was removed and then reloaded without resetting the players quest. Ideally you wouldn't want to reset the player's quest, but then how would you be able to keep the quest steps consistent? I suppose I could try to keep the old quest running using the old parameters and only change the data on new quests if thats what you guys want.

One thing I forgot to mention, if I did change it to where it was using the old information, EVERY quest would keep a couple of the LUA script in memory. That is unless I implemented some complicated version system, but I dont think it is worth it.

I would say make everyone's quest reload to the same quest. This way everyone is on the same page and nothing gets corrupted.

If the problem is only exposed because a server admin changes the original quest script to something new, then I say flash the old quest completely (if incomplete). How often is that really going to happen? If it's during development of the script(s), no player should actually have the quest anyway. If it's after the fact, oh well. Should have done a better job writing the script in the first place.
If I am way off on understanding your issue, then sorry. Scripts/Quests are not currently my strong point here... I am a DB guy. I just... DB. But I always have opinions, yes indeed.