The only problem I see with using Directory is that I can't see theI see it with both sources.
The problem I see is that if the group is at all busy it will no longer be /the/ "Most Recent Successful Delivery" by the time you look.
On the other hand, /not/ being in the Recent Bounces list is pretty good evidence that the member's email service accepted the message. At that point it should either be in the member's Inbox or his/her Spam/Junk folder.
I'm assuming here that you are a mod or owner of the group in question and can see the Members list and look at a member's page.
I asked them to check their SPAM nothing was in their SPAM from me.Maybe they didn't recognize it as "from you". When sending from the Directory (or the Members list) you have an option for whether the message says it is from "you" (your personal email address) or from your group's management (the group's +owner address). From the group is the default.
Or, depending on what email interface they use, they may not have known where to look. If they're reading emails using an application like Thunderbird or Incredimail on their PC then the message could be languishing in the Spam folder at the email service's webmail interface, not the Spam folder in their email application.
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