The idea they've talked about consistently is gleaning what lesson and what reflection the symbol of your physical experience can offer you. In other words, what can your physical experience reflect as far as a lesson, such as unconditionally validating and loving yourself, letting go of responsibility that isn't actually yours, being with an unpreferred energy you may have been denying is there so that it can transform and you can consciously define yourself from a neutral space.
They basically have said integrate the lesson, act on what you have learned, the reflection may not need to show up anymore. But there's no need to insist, because if it does, there is still something positive you can glean from it even if it's objectively not your highest preference, this can still act as a step on the stairway that you can validate fully and gain something positive from.
So from this whole perspective, it doesn't have to be about believing the past doesn't cause the present if that's a big leap for your physical mind. Rather, it's about COMPLETELY grounding in the present and asking: "What is this reflecting to me now?"
From the 4th density perspective I relate to, the past is a tool we create to experience a certain reality and set of relationships in spacetime. It allows us to fully revel and experience our current physical (or quasiphysical) exploration. We don't go into a more 4th density perspective by insisting that the past isn't real, but by letting go and letting ourselves dream, feel, be in the present, and be with whatever excites us. So it's really just about being present and open to whatever realities are coming to you now. If you can daydream and be fully involved with the reality, the idea, the feeling, the timeline where you don't have this scar — without insisting on any outcome, this may be the way to enjoy the present and utilize 'time' to your favor rather than against your preferences :). Enjoy daydreaming and feeling it, you literally are becoming the You who is in that timeline as you feel into it and imagine.
Time is something we created as spiritual beings to have an experience of change and have an experience of story, identity. Enjoy the dream as fully as you can :).