Thank you so much for the reply, and i am aware that this question is a long-shot. Nevertheless i noticed that the github repo for ScrollMagic was somewhat quiet, which gave me the idea of trying here, since i have had some very good experience with friendly people, just like you, replying with a possible resolution for this problem.
Its super interesting with the paused parameter, but i am not quite sure where to add. I tried just adding it on the first scene (anchor1) to the to part of the animation, which did not work. If i set the paused to all the tweens it does not move at all.
Its probably very important that i explain this is a minimal version based on a very big project, where i am only experiencing the problem with the video background. Everything else is working as it should.