Result of the investigation: The CampaignBuilder creates the object graph correctly (although there was one missing test). The URL parameter handling works as expected. The Errors came from another source:

Campaign dates built by the CampaignBuilder were always in the UTC time zone (because of the time zone conversion between the time zone from the configuration file). On servers where the default time zone was not UTC, this leads to errors in Campaign::isExpired.

The solution to this problem is introducing the CampaignDate class that enforces a UTC time zone and does time zone conversion when given a string and time zone.

The PR for this solution is here: https://github.com/wmde/FundraisingFrontend/pull/1406 But that should not be merged before 2019-01-02 (because the FUN team is not present at the end of the campaigns, where we could quickly react).

A short-term solution is to extend all the campaigns. PR for that: https://github.com/wmde/FundraisingFrontend/pull/1412