Nevermind... I found the solution in a few other forum posts.
Here's the link to the forum post that helped me resolve the issue.
I used the registry method. My scheduled task was running under anohter AD account created just for services and scheduled tasks. I connected to the SFTP server using the GUI under my account, which logged the key from the server in the registry. I then copied the registry key mentioned in the link to the other accounts user area in the registry. I could have also logged into the server under the other account and used the GUI to connect. This would have also stored the server key in the registry.