The de Persia bailer works by venturi principle only when the boat is moving. It will not self bail at the dock or mooring. (It also sounds like the ball has shrunk or the cage holding it has disappeared, but that is a different issue). The second hole about 4" up the transom is the mooring drain for when it is left on the water. Close the self bailer at the mooring but open the mooring drain. The rainwater/waves/splash etc will enter the cockpit but only to the level of the mooring hole, then will drain. The sump at the back of the cockpit collects debris, as the cockpit is tilted slightly back when there is no one aboard the boat. The hole of the mooring drain is very close to the waterline so as soon as you step aboard, water will start coming in. Plug it and bail, or start sailing, and open the de Persia bailer.
As indicated earlier, the ball in the de Persia bailer was designed to prevent water coming up during slow speeds, but in actuallity it does not work well, if at all.
Check the first two pictures in the gallery for these two separate drains with two separate functions.
gallery/search.php?user_id=4