My opinion would be to NOT reach under the comforter and NOT try to pet her. Nothing looks normal to her and nothing has her smells on it.
Go in the room and spend time with her on the floor. You are much more frightening when you are tall.
Don't look at her and don't acknowledge her. Let her be. Read, work on a computer, sing (softly),
work a puzzle, etc.
Leave a treat on the floor where you (and now your scent) were sitting.
Use a wand toy to entice her. Again do not try to touch her.
Try to keep a schedule because you know how much they depend on routine.
Leave a dirty shirt that you have worn next to her food dish.
Use a Feliway plug-in. Maybe try Rescue Remedy in the water.
She will do better in one room now. It will help her to feel safe and the room will start to smell like her.
Give her time, lots and lots of time.
Expect nothing from her. Let her come to you. That will earn her trust.
Not a good example, but imagine if you were two years old and taken to another country. You can't understand the language, nothing smells like your room or family, you are confused and scared, you want your mommie and don't know where she is or why she left you there. THEN a stranger trys to touch you and hold you! You don't know if these strange people are going to hurt you. You don't understand.
In time she will understand and see that you are bringing her food and not trying to harm her.
Where ever she goes, the caretaker will need to give her patience to adjust on HER terms.
So glad you have her and I am sure she will feel better.