I had the same situation. I had a number of old groups that I needed to create galleries for. Here is the SQL I used in phpMyAdmin:
INSERT INTO wp_bp_gallplus_albums (
owner_type,
owner_id,
date_created,
title,
description,
privacy,
group_id )
VALUES
( 'group', 1, '2013-03-13 15:26:34', 'You Say', 'You Say', 5, 2),
( 'group', 1, '2013-03-13 15:26:34', 'Love Is Alive', 'Love Is Alive', 5, 3)
If your database tables don’t start with “wp_” then you will need to change table name prefix after “INSERT INTO”
You can add an additional set of values, as I have shown, by just adding a comma after the last one I have and then a new set of values in “( )”. The last one should not have a comma at the end (same as my example)
Make sure your “owner_id” and your “group_id” are changed to be the values for your user id in WP and the id of the group you are creating a gallery for, respectively.
Hope this helps.