Not even the article you cited (which has been widely and justly criticized) found any evidence that the house she Rachel was protecting concealed any tunnels. As one example of how factually challenged the article was it questioned whether the house Rachel died protecting was actually in line for bulldozing - when in fact IT WAS BULLDOZED. And there are lots of descriptions of bullets coming through the walls and corners being knocked out from other sources; there was no question of it being scheduled for demolition. More to the point though, even if you accept the article as completely accurate (it was as sloppy a bit of second rate journalism as MJ ever published), if you had bothered to read the article all the way through you would have discovered even from THAT ARTICLE that the answer to your question "But was she, witting or not helping to protect tunnels smuggling arms?" was "NO". I long ago figured out that you don't always read the articles you link to. But really you should read articles you link to as backing for your points, or that you cite to raise questions.
Gar Lipow In Olympia, Washington - Home town of Rachel Corrie Helped raise money for a house to replaced the bulldozed home Rachel died trying to protect.