I'm sure if Mike Dolce helped Johnny Hendricks cut from 215 to welterweight and Rampage cut from 260 to light heavyweight then he can help get Cyborg from the 150s to bantamweight. Also who is this doctor we are talking about?
He helped them to cut body fat, but Santos has almost no body fat. And in the heigher weight classes, it's much easier to cut weight anyways. And as Hammerlock said, she'd be close to underweight.