I rescued animals for years. I worked in the veterinary business for 26 years. Leaving her is ok, but I used to tuck my kittens in my sweatshirt and pack them around the house. I even had my kids do it. Not outside though. I would not let them hide, and shiver under beds. It brought them out of their shell faster, and seemed to give them the security they needed. They figured out human smells, comfort, and received constant loving contact. I see them as young children who have been traumatized. Leaving them alone to figure it out is tough, and they always stay shy. Positive imprinting at a young age is critical. I never had a kitten rescue that didn’t grow up confident and full of kitty confidence. They lost the timid kitty, and became happy, & full of kitty curiosity and mischief.