know that they share the money with all non-BCS conferences as demonstrated in this section:

Now consider the years a team from our conference goes to the BCS. Last year was the largest non-BCS payouts ever because 1 team went as an AQ and one team went as an at large. A total of $24 M was paid out to the 5 non-BCS conferences and was split as follows:

$9.8 million Mountain West (TCU was the non-BCS AQ)
$7.8 million Western Athletic (BSU was the non-BCS At Large)
$2.8 million Conference USA
$2.1 million Mid-American
$1.5 million Sun Belt

And I'm not claiming to have all the answers...just trying to give a broad overview with some facts/details.

That said it is pretty close to reality - with the exception that someone else brought up that the MWC may allow for expenses to bowl teams be taken out before splits are made. I don't actually have a source to say one way or another. I just cited the SI article's method....