Hi Andrew,
Thank you so much for visiting the Disney Parks Moms Panel with your question! Sounds like you have a really fun day planned. A visit to
Disney's Animal Kingdom, followed by an evening at
Disney's Spirit of Aloha Dinner Show, will include so much entertainment and excitement!
I recommend that you be at the bus stop at Disney's Animal Kingdom waiting to catch a bus back to
Disney's Polynesian Village Resort no later than 90 minutes before your reservation, so at 3:45 p.m. This will give you time to wait if you need to wait for a bus, and to take the ride back to your resort. This assumes a quick freshening up in your resort room - perhaps around 20 minutes - and that you then head on over to Luau Cove to enjoy an evening of entertainment, merriment and good food.
I hope that these thoughts are helpful for you, Andrew. Have a great time planning your magical vacation, and please do let us know if you have any further questions.