A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
viewtopic.php?f=59&t=59400&p=764874&hilit=Aroru#p764874
Based on this topic if I target Shosuro Aroru Exp. with a Hired Killer and he redirect it to one of my Personalities must I pay the costs and kill my personality or I can avoid that?
I think I can chose not to pay since the target was changed but I'm not sure.
[Mod edit: Slang removed. -ZF]
(I)f I target Shosuro Aroru Exp. with a Hired Killer and he redirect it to one of my Personalities must I pay the costs and kill my personality or I can avoid that?
Point: There is no such thing as "redirection" in Samurai Edition rules.
The Experienced Shosuro Aroru's Reaction is "when" targeting occurs. Hired Killer's cost is set after targeting occurs (http://rules.l5r.com/Rulings_H#Hired_Killer).
The cost did not change, and you must pay it.
See also: viewtopic.php?f=59&t=61363 viewtopic.php?f=59&t=61353
Though the timing of Misdirection is earlier, same basic principle is at work.