In the federal system, the most that an inmate can earn for good behavior is 15% off of their sentence - so the best behaved inmates serve 85% of their sentence. If the feds can get one of them to testify against the other (probably the boyfriend against Elizabeth), they may offer that witness a deal for perhaps 3-5 years. But at least one of them is going to do over a decade. Anything less would cause a huge PR problem for the US Attorney's office for the Northern District of California, precisely because she is well connected. They'd be accused of doing favors for a formerly wealthy, well connected person.