In universe, it is not ok to kill Rudolph. But as readers of a fiction work, we can suggest things that happen in tbe books that we wouldn't advocate IRL. For instance, killing Rudolph with extreme prejudice.
In universe, it shouldn't happen, for several reasons, one of those is Rudolph did not want to kill Karrin, it was an accident (or divine intervention).
But we are allowed to hate a character. I see it a little like many years ago when a lot of Star Trek fans wanted to will Wesley Crusher