How is running a few SQL queries difficult. And I don't understand why you are mentioning vanilla client, it has nothing to do with the client. Characters are all in the database. If you mean that clients of other players need to be updated properly that can be solved by doing the race change by creating a level 1 and copying all char info to that new char and deleting old one, while removing race-specific quests if there are any. All this can be done automatically via a script, just make sure user is not logged on (just like for the unstuck feature on website).
I mean sure, it requires some time and they may not have it or they may be doing something important at the moment, that I can understand. But I don't see why you keep saying that it would be difficult.