The SCAR outpost event chain breaks during the “Help Terrill reinforce the camp with scrap metal barricades and cannons”. You are able to build all 4 cannons however you can only build 4/6 of the barricades with 2 of them never appearing. I have completed the same event up to this point 3 times today and it stopped at this point every time. This is quite frustrating for those who require the daily provisioner token from Terrill Tinkerclaw who becomes available at the end of the event chain.