Not perfect but a good work around:
To find all of the photos contributed by any group member, start by clicking on the narrow box to the right of the buddy icon. Click “Send Flickrmail.” (you won’t be sending any mail). In the browser window, locate the member’s ID; it will consist of 12 characters, 8 numbers, @N and two digits.
(NOTE: Some older IDs will have fewer than eight digits.)
Highlight the ID by clicking and dragging your mouse. Do not include the slashes ( / ).
Copy to your clipboard (CTRL-C).
Go to the first page of your group’s pool. In the browser window, paste the ID to the end of the URL (CTRL-V). Click “go” or the arrow, depending on your browser. This will display all of the photos in the group pool added by the member (via flickr help forum)