There are only 3 switches involved in kicking the ball out from the outhole. A switch on the O relay makes the score motor turn (that's obviously working), then these 3 switches need to be working correctly. If one of the 3 isn't closing, you'll have to figure out why.

Surf Champ ball return (resized).JPG

The problem might be that the machine is stuck in bonus collection mode, keeping the score motor running via the bonus score relay. When the bonus unit counts down to zero, a zero position blade switch ( probably a make/break switch ) will transfer power from the bonus score relay to the O ball return relay, allowing the ball to be kicked out from the outhole. Clean and adjust switch if needed.

You can also inspect to make sure both wires are still soldered to the terminals of the out hole solenoid. A broken-off wire or poor solder joint could result in your issue.

Alternatively, you could use jumpers to directly send power to the solenoid terminals to verify the solenoid is functional. I've jumpered from the coin reject coil inside the coin door before, but even using a 9V battery should make the plunger at least twitch.

There's that BX saying hi again!