I had the same confusion in the beginning. The BSI is responsible to fix the infrastructure, to report on the problem, etc. You might not be aware of the discussion regarding the Federal Office for the Protection of the Constitutions involvement.
Not sure about your agenda and why you spill inaccuracies and distort what articles say with a tendency to promote Russian SWR goals.
1. The problem arose because the parliamentarians did not use experts from the BSI but have no clue but do it on their own with their own people. The BSI protected government network is not affected.
2. The German interior intelligence agency is not "involved" as you put it - what agenda do you have? - the article says parliamentarians need to decide if they want to ask the counterespionage department of the German interior intelligence agency, what some don't want.
Remeber that this is not about the BSI.
http://www.spiegel.de/netzwelt/web/cyberattacke-auf-bundesta...