python-scripting the baking animation sequence with additive layer tracks

Hello fellas,
I wrote a tool that export animation sequence/s in an .fbx file. It works just fine until the animation sequence features additive layer tracks, in which case the exported animation is the basic animation without the tracks.
It seems that there is not a method nor a class that allows the backing of the layers in the file.
Is there any option to achieve my goal (other than scripting the baking from the sequencer)?
Thanks in advance for your help and have you all a wonderful day.