Hi Kristin,
You have a couple of options really depending on what the Park Hours and Extra Magic Hours are at the Disney Theme Parks during the dates of your visit.
Theoretically, you could take a bus from
Disney's BoardWalk Inn to the Magic Kingdom Park where you would need to transfer to a boat or monorail over to
Disney's Polynesian Village Resort.
Likewise, you could take a bus from Disney's BoardWalk Inn to Disney's Animal Kingdom Theme Park and then once there, transfer to a bus heading to Disney's Polynesian Village Resort.
Another option would be to take a boat from the BoardWalk Inn to Disney's Hollywood Studios where you would need to transfer to a bus back to Disney's Polynesian Village Resort.
If it is really quite late and the Disney Theme Parks have closed, you can always catch a bus from Disney's Boardwalk Inn to
Disney Springs where you would need to transfer to another bus heading to Disney's Polynesian Village Resort.
Wishing you a magical trip filled with memories which will last a lifetime!
Emma