Congratulations, JK! Now that Kiki’s had a night indoors without being terrified you are well on the way to her moving in properly.
My own experience adopting Flicker. He got the name because for months all we saw was a flicker of skeletal black cat. After some months of coaxing I could pat him and he’d moved in to the extent that he didn’t leave the garden. He would come very diffidently just inside the back door to eat, but he always slept under a bush in the garden – wouldn’t even go into the doorless outdoor laundry where I’d tried setting up a comfortable box. Then one night it was pouring rain, so I put a blanket on the floor just inside the door, near where we put the food, picked him up, brought him inside and pointed to the blanket. He looked at me very doubtfully as if asking if it was permitted, then curled up on the blanket. After that I could bring him inside to sleep, but he didn’t venture past the blanket. A couple of weeks later he got the courage to go one room further into the house and discovered couches and armchairs. From then on he was a domestic cat.