I managed to solve my problem a while ago so I thought I would post an answer in case people are still having issues with this. Prior to 4.13, you could tell the AI to move to the same location every frame and it will work fine. However, now, you need to only call it once, otherwise the movement functionality in the AI classes will reset each time - hence my enemies standing still.
I added some logic that only called the AI move function if the distance between the player’s location and the AI’s player “known” location is greater than a set threshold.