Well, I just don't it's a great idea. If Simba doesn't care for kitties, I think you're just asking for trouble.

Humans tend to be forgetful some times. Cats tend to be curious all the time. With that combination and knowing that Simba has some kitty issues, I think it's a deadly combination. The enclosure door will probably be left ajar at some point (things happen). Kitty will be curious and so will Simba and it wouldn't be a good outcome for kitty.

Kitty deserves a home where it doesn't have to be afraid for its life. Simba deserves a home where the kitty hunting instinct doesn't cause trouble.