I uploaded the mission.pbo into directory, I can see it in #missions, but it doesnt load when i click on it
On Arma 3 there's something very usefull and nicely done by the dev, that's the ".rpt file" you can have access to it in the "logs files" of your webinterface and see what's gfoing wrong, why your mission won't load)
I see that you don't use mods on your server and you want to launch this mission, be sure there isn't any mods required, be sure that the mission is still playable and not too old.
Check your ".rpt" in log file, it will tell you what's wrong, really, when your are connecting to it. Do you see the slots during the lobby of your mission?
Also checked on Steam workshop, mission is playable : https://steamcommunity.com/sharedfiles/filedetails/?id=1775053830&searchtext=dynamic+civil+war
For me the problem is not server side problem. (Your server is working great right now too)