Maybe get her a new Catnip-fill toy, put some catnip in it, scrunch it around in your hands and lay the toy in her spot or anywhere on near it. She will most likely start a love affair with that toy. Not play like you're wanting to see, but it really is a joy to watch them cuddle up to a soft catnip-filled plush toy.
How old is she? I really don't know when the hunting instinct kicks in. I haven't had kittens in decades, so don't recall when I noticed them learning to play. Maybe she just needs to feel more content with exploration before she starts feeling safe enough to play.
She might be a bit young to react to catnip - most cats don't really start getting an effect from it until someone after 6 months.