Lord Vader Joins the Wrong Team - Order 66 Raid Graphics Issue

Last time I checked, Lord Vader is not a playable unit in the Order 66 raid. Imagine my surprise to see him standing on my side, long-distance force-choking a Jedi. See my screenshot. He’s standing on the right side, overlaid with one of my characters. 

On a subsequent attempt with my Jedi Master Mace squad, he was standing in the correct place. I did not test again with the same squad as I managed to max out my score and didn’t want to restart.