According to the lack of new info, what about a little bit of "brainstorming"?
It is a proven fact, that CB had a connection to Braunschweig (Brunswick). Although we know that this connection is related to a timeline from 2012 or 2013 and on, we do not know, if there was an connection that could predate these years. What we know is, that he boasted around transporting children much earlier and he frequently travelled between the countries.
I found and old article about a couple that ran residential groups for children in the town of Gifhorn, what is very close to Bunswick between 1998 and 2007. They have been arrested and imprisoned for abusing these poor kids for years! According to the following link, the couple has been in charge for the group for about 25 years.
Missbrauchs-Vorwurf gegen Gifhorner Ehepaar: Diakonie will jahrelang nichts gewusst haben
This residential group was hosted by the....again..."Diakonie". Same institution CB grew up with, has been related to in Portugal and where little Inga went missing as well.
Of course far away from a concrete relation to the case and the suspect, but another remarkable coincidence as well. And that case became public in 2019.....
Just a thought, but maybe it could fill the void!
PS: The "Diakonie" is a big clerical institution. I would like to ask again, who is paying CB's expensive lawyers?