This is NOT a cheat. This is a VERY difficult shot to get and if you want to get it honestly, you just need to keep trying.
Step1
starting point
Place the ball to the far left.
Step2
aiming and release
Aim for the far right by the outside frame of the lane.
Step3
curving the ball
Before it gets to the gutter, press and hold down the left mouse button.
Step4
Keep working at it. This is a difficult shot and I still don't pick up this split most of the time.
Remember, it doesn't hurt anything to try to pick up this split. Worst case scenario, you get 8 pins instead of 9 - but as long as you try you might just get that spare!!!