I have the same problem as you and do not seem to have a solution or a type of support for the creators ...
I found something but I do not know if it works.
https://github.com/ike3/mangosbot/issues/45
I took a look at this old problem: https://bitbucket.org/lordpsyan/trinitycore-patches/issues/313/ike3-playerbots-playerbot-system-is
Open my configuration file and code my complete path within /Users/username/server-directory/bin/aiplayerbot.conf
And now it seems to work. My world server is processing the robots at this moment ...