Yeah... she ate that

[Bogertophis]

Hmm... Well, all my geckos eat their sheds, so I guess it isn't out of the ballpark that a BP would eat theirs to regain nutrients.

Also a thought, maybe the shed contained some poo or residue (mine often do) and the poo smelled of rat causing her to eat it for that reason?

Or if fed live, the shed could have smelled of rodent urine from when the snake made a kill?