Hey Constantin,
Thanks for such an awesome reply. Sound guys represent! We were also shooting with an FS7, scratch track was just fine on that camera, it definitely wasn't the 411a, but I just hate finding an issue and not having a solution for it. I do feel like it's on the camera end, and most likely something with the Weapon's internal settings. 99.9% sure it was actual time-code signal embedded on the scratch track though which is just really odd.
You're also right, scratch track is more a personal preference and really isn't needed especially when TC is sync'd, but for the future I'm always interested in finding a workaround just so everyone can be happy.