Hi Meredith,
It sounds like you have a great vacation planned!
Disney's Polynesian Village Resort is wonderful. The tropical Pacific theme is lush and immersive, and the location on the monorail line is so convenient.
Sanaa, located at Disney's Animal Kingdom Villas - Kidani Village, is a great restaurant! The African fare with Indian flavors is delicious, and it is great to be able to see the animals on the savanna right outside of the restaurant.
I would leave yourself about 30 to 45 minutes to get from Disney's Polynesian Village Resort to Disney's Animal Kingdom Park. This would include time that you needed to wait for the bus as well as the ride. Then, as you know, you would need to take another bus from Disney's Animal Kingdom Park to Disney's Animal Kingdom Villas - Kidani Village. While this is a short ride, again you may have to wait for a bus, so I would allow about 30 minutes for this leg of the journey as well.
If you are already spending the day at Disney's Animal Kingdom, heading to Disney's Animal Kingdom Villas - Kidani Village at the end of the day would only be one bus ride. Then you would need to transfer transportation on the way back to Disney's Polynesian Village Resort, or you could ask a cast member to call a taxi for you. This would come with a cost; however, I have found taxis to be quite reasonable on Walt Disney World property.
Another possibility for you, if you would like an exotic dining experience without leaving Disney's Animal Kingdom Park, is to try
Tiffins. My family recently dined at this location and we loved the international food and decor.
Please do let us know if you have any further questions, Meredith!