They don't spawn at all during / after the skirmish but you can still find them later. I tested it with my Storm Sorceress. Only Elegis and Kaldani hide a little further up out of fear... Arka and Memnos only appear near Sazza in the prison. It's a shame if they secretly got scrapped on the defense weir bcs they cant fix this encounter...


[Linked Image from i.imgur.com]