Okay, I made a video...I shot the right orbit repeatedly, and edited out all the dead space, so I have a video that just shows a series of shots up the right orbit. Most get rejected. The first two and a half minutes show approximately 22 shots at regular speed, and then the video shows the same shots at half speed. The half speed video is revealing. Although the rejects vary, there is one thing that seems to happen consistently: a solid right orbit shot skates across the rubber along the top of the playfield, and then strikes the metal guide just above the saucer...from there, the ball ricochets downwards into the gate for the reject (examples at 7:07, 8:20 and 9:24). Even some of the balls that don't get rejected seem to bounce off the ball guide above the saucer and then ricochet off the gate, but the gate sometimes bounces them into the saucer.
Based on this, I see two possible fixes: bend the ball guide above the saucer upwards to reduce the angle of downward ricochet, or bend the gate wireform to try and get the ball to bounce upwards into the saucer instead of away from the saucer.
But, I'm open to better ideas...I'm not sure "bending" metal is the bestI would suggest examining the ball guide in the right orbit to see if it reveals any clues as to what the ball is doing. For example, it may not look like the ball is getting airborne, but the ball guide may suggest otherwise. It could also indicate if the ball is bouncing at a consistent spot that may give you an idea how to shape, bend, or otherwise adjust. Take a look at my post #4862.