First of all, the *_these_nonmember checks are not case sensitive.

Then, I don't see a way that Mailman could notify the poster and admin that a post is held and then deliver the same post to the same list without further action.

What is in Mailman's vette log from this time frame?

You are correct, the Vette logs show that the moderator did approve the post -- assumingly, by the web interface, as no log of such appears in the mail logs:

Jun 17 10:22:11 2015 (1447) Cyber post from dxxxxxx@zzzzzz.huji.ac.il held, message-id=8580F77FFEF0F2448E3A51C4AE83807D011951BABC@Pegasus2.hustaff.huji.local: Post by non-member to a members-only list Jun 17 10:24:56 2015 (88042) held message approved, message-id: 8580F77FFEF0F2448E3A51C4AE83807D011951BABC@Pegasus2.hustaff.huji.local

Using the list's archives, I tracked down the problem -- the information the user relayed to me was incorrect. Apparently, the user sent to the list with the following 'From:' line:

 From: dxxxxxx at zzzzzz.huji.ac.il (Dyyyy Swww)

Sorry for bothering the list needlessly.

Ephraim Silverberg, CSE System Group, Hebrew University, Jerusalem, Israel. Phone/Fax number: +972-2-5494521