Headquarters mode being down is especially frustrating because a few of the Daily Orders you can get, which give you rewards when you complete them, are dependent on being able to interact with other players. If you’ve taken the order to commend another player or beat another player in 1v1, you might as well abandon them for now. You can’t complete them without meeting with others in your HQ.
For now, it seems like until the Call of Duty WW2 server situation gets under control we might not have access to the full benefits of Headquarters mode. If past Call of Duty launches are any indicator, expect it to be a week or so before the bugs get ironed out.