That's an unreliable way to test your span.

Do this.  With the ball resting on a ball cup (or something) holes up, insert your thumb all the way into the thumb hole and then lay your fingers across the finger holes.  Don't reach far or stretch, just lay them there.  Your crease from the appropriate joint (fingertip or conventional) should land halfway across the hole.  This is an easy way to test span only but it's a start.

Depending on the length of span, length of thumb, and joint flexibility your driller will hopefully get you close on the pitches (angle) of the holes. 

The more you stretch your span, unnaturally, the harder it will be to get your thumb out of the ball fast enough.  For that reason if there's a "miss" I prefer it be a tad short rather than long.  Any competent driller can "hit lines" and drill a ball, but fitting hands well takes lots of experience.  Good luck.

The index finger?  The one that doesn't go into the ball? 

You'd better see someone who can look at things then.  If both spans are correct and if your pitches are appropriate then the ball rests where it rests.  If you want to stretch one of the finger spans, or even shorten it, I'm sure you could change where you feel the weight of the ball.  Assuming you're not having any trouble getting out of the ball now, you could make things a lot worse before they got better. 

Ron Clifton has an article called Finger Dancing that might provide some options for you. 
http://www.bowl4fun.com/ron/tip11.htm

It gives you some ways to change the roll by moving your first finger and pinky around.  How far you spread your index finger away from the middle finger can contribute if I understand correctly. 

Sorry I should have specified more.  I am trying to have a discussion as much as anything about this.  Ive drilled my own stuff for the better part of the last twelve years and my span is personally changed because of a finger that doesnt straighten all the way.  my questioning come more from the stance of I have watched my friend who is a no thumb bowler for the last 14+ yrs very good bowler and as of recent have watched many  of the two handers that have become popular.  Everyone seems to talk about the power  and so on that they are able to generate and i know the technique and mechanics behind it.  At the same time there has to be some accounting of the fact that resting  the ball on there palm makes it to an extent allows for easier/quicker cupping and uncupping of the wrist as it rotates.  it seems that this part of their deliveries could potentially be simulated if there was a way with span and pitches to achieve something similar with the way the ball rests.  I know the initial thinking is well it should rest on strong side of hand but at the same time it also use to be the norm to have one finger hole plus a thumb.   or only drill a certain way. 

Sorry I should have specified more.  I am trying to have a discussion as much as anything about this.  Ive drilled my own stuff for the better part of the last twelve years and my span is personally changed because of a finger that doesnt straighten all the way.  my questioning come more from the stance of I have watched my friend who is a no thumb bowler for the last 14+ yrs very good bowler and as of recent have watched many  of the two handers that have become popular.  Everyone seems to talk about the power  and so on that they are able to generate and i know the technique and mechanics behind it.  At the same time there has to be some accounting of the fact that resting  the ball on there palm makes it to an extent allows for easier/quicker cupping and uncupping of the wrist as it rotates.  it seems that this part of their deliveries could potentially be simulated if there was a way with span and pitches to achieve something similar with the way the ball rests.  I know the initial thinking is well it should rest on strong side of hand but at the same time it also use to be the norm to have one finger hole plus a thumb.   or only drill a certain way.

There was an article by Joe Slowinski awhile back that discussed the idea of a different layout/ball fitting thought that would have the ball sit more on the palm. In essence, it dealt with extreme side pitches on the thumb and such. Google it...be an interesting read for you.

That was called the Anatomical Drilling Technique.

https://www.bowlingthismonth.com/bowling-tips/an-anatomical-approach-to-fitting-and-drilling/

There are some youtube videos out on it too.

http://www.ballreviews.com/drilling-layouts/anatomical-drilling-technique-t307355.0.html

At what point do consumers realize something that's a scam?

 
When you try it out on a ball and realize it's a scam. 
 
Some things you just have to find out for yourself. Over time, you learn to see the gimmicks for what they are.

He uses generic gripping angles not taking the individuals hand into consideration
I'm sure if you fit enough people you'll have a few that'll have success
I don't care for snake oil salesman no matter the alleged credentials