I performed a dominate person with the Ring of the Lord Inquisitor on an orc shaman in the arena dungeon. I was intentionally walking the shaman next to enemies to get them to trigger attacks of opportunity. I target moved the shaman past an enemy, it got hit, the dominate mind ended from the hit and the shaman completed it's move. I no longer was able to control the shaman and there were no buttons for me to end the turn. I pressed num enter as well to try and end the turn but had to load a save as I had no way to end the shamans turn. I waited for about 2 minutes to see if the shaman AI every took back over to end the turn but it didn't.
I just encountered a similar experience. The dominated target triggering a new Wisdom saving throw and succeeding on its turn prevents the player from being able to give any further combat instructions.