I suspect the IRS will be interested in her too.
I suspect the deal she's being given is "tell us everything you know, and we won't hand you over to Guido the IRS Collector"
If she wasn't paying her taxes, and she may very well have been, she's probably been immunized for her testimony.
And it's probably a heck of a deal for the taxpayers. Cheap at 100X the price to get such a bunch of slime put away.