During a Karl Franz campaign, the event 'Norscans Attack Elector's State!'
event fired, targeting the settlement of Fort Soll under the ownership of The Golden Order. Selecting the 'Send a Military Force'
option, the battle was entered.
Upon battle starting, the player-controlled reinforcements given to the battle appear on the edge of the map but path into and around a tower on the edge of the map. After several moments of this happening, the units teleport into the map and are controllable. Before this point, the units cannot be interacted with via normal means.
Any further information I would be happy to provide if needed.