Thank you for the reply @Harald. I will give that a shot and see if it works.
FYI, getting the latest 3.6 unitypackage didn't work. I'm still having the issue where the sword object is rotated randomly during the downward attack animation. I will continue to investigate and post a solution if I can find one.
Okay, so I got it to work. For every animation, I had a keyframe for every bone on the first frame but did not for the last frame. I added a keyframe at the end of every animation and then turned off "Auto Reset" in the inspector window for the animator. That did the trick. Hopefully, this helps someone else out there and saves them a little bit of time!