Bug/Issue i can not pass the mission : miniknog stronghold

hello everyone today i try for pass the shit mission after Apix Cludes
so i deploy for mission then i will go and finished this(killing boss and .... ) but at the end i can do anything i saw a video in youtube than show before killing the boss that monkey man who you speak with him in a first place should run but when i go there still i see that man try to espace(its bug for sure) he and his gruop cant escape whan can i do ? i am playging multipalyer not single sorry for bad english