Its a rat that is a bright white color. She's either going to terrify some old lady or get picked off by a hawk/dog. And I think your neighbors will have an issue with her eating their cats

She's not been exposed to much disease in her life, as she's been in your care, so when she goes out her body is going to be assaulted by everything and her immune system probably cant handle it, so there is that to think of.

The easiest thing to do would be to throw her in a box with a piece of dry ice in water.