Well, after some more tinkering I got it working. I'll go ahead and say what seemed to make it work so that someone might get something out of this post.
First, I changed the import on my one shot sound to not import as the compressed format (set compressed to "disable"). Then, I changed the looping sound to play using the StreamPlayer instead of the SamplePlayer. The bonus of that is it made it easier to manipulate the sound as it plays.
One aside, I was able to figure this out by looking at the jam game Ball Basho(https://itch.io/jam/godotjam122016/rate/106873), which had working audio and had the code uploaded. Thanks.