Seems there is currently none of the monks involved with Outlook deeply enough. And then Outlook seems a bit diffident about senders' addresses. Google found this, which may be of help to you although it's not Perl...

Update: tried it out myself, you get more or less sensible results if you replace $message->From() with $message->SenderName(). If you really want the address, $message->Sender()->Address() worked for me, and SenderName() seems to be an alias for Sender()->Name().