They typically review the business returns as well. As you’re no doubt aware, the CSS and the supplement does a very poor job of capturing the true state of most businesses. The tax return is really a better source.
Adjustments might be made on the business side of things beyond just deductions. Treatment of inventory, liabilities, cogs, etc might be reviewed. I’ve seen cases where s corp distributions in excess of business income were treated as personal income (not something someone who understands pass through entities would think could be the case, but it was).
Or they might have misread something.
Of course, the revised offer is still a bit of a mystery if everything was provided at the same time. I’d think typically they wouldn’t release the award info until everything was reviewed, but perhaps some sort of internal snafu that was corrected once the “business tax” person reviewed things. That’s one possible explanation, not necessarily the correct one.
I’m not clear on why an ED admission would still be on the table here but maybe that’s a separate issue.