I had this same issue and the way I got it fixed was doing the Bunker mission again but do it with someone who hasnt completed it yet. You can usually matchmake to find someone and make sure they havent done it before. Once you finish the mission have them immediatly go activate the network at the white house. They have to watch the full cutscene and after they do that the mission should complete for you.
An update if it helps I had the same issue with not being able to reactivate the SHD network after the mission on xbox 1. I tried logging in and back out, restarting the game, power cycling my console nothing there helped. I even completed the first two strongholds and got to level 30. (28 when I did the mission) and still wouldn't work. I tired what MCCLEGEND1996 suggested it took a bit. Had to create a post on xb1 for division 2 LFG to find someone (actually multiple people) who hadn't completed the mission then they were able to go back to the base and watched the cutscene. Which after that I got a mission complete alert and the message to activate the network went away.
I have this issue too, struggling to find someone to group with though.
When i encounted the issue it went like this
- In someone elses group
- Able to trigger the SHD Network reinitialise cutscene, but i get a black screen and the game hard crashes.
- Upon revisiting after starting the game again I am I trigger the reinitialise of the SHD network, the game pauses for about 10 seconds I get the see the majority of the cutscene but it finishes early.