Did the IDF state before the particular operation that they were going after tunnels? I don't know if they did or didn't. Even if they did, what kind of proof could one offer to say that Corrie was aware of such a statement if it did, in fact exist? There also appears to be no way to confirm that any Palestinians "clued her in" as to the existence and/or placement of said tunnels. I do think that it is safe to assume that Corrie knew she was defending and siding with armed persons. I don't buy the claim that somehow idealistic ignorance was the contrubuting factor in her death. She chose the wrong side and arrogantly taunted a force greater than herself assuming that a number of factors (including fear of bad PR) would keep her safe.
Did she know about the tunnels? That's not a fact that anyone can seem prove now.
Exactly right. Which is why none of us can cite Corrie's knowledge of said tunnels to justify their gloating.