based on this post, i have the same question.
How to workaround, doing every Matinee animation at the final actorposition?
https://answers.unrealengine.com/questions/9143/how-do-you-make-actors-move-relative-to-position-i.html
Greetings Stefan
Edit: sry guys, just found that easy way Matinee "world frame" and "relative to initial" - World Creation - Unreal Engine Forums