Hi SnowFleur,
this post that doesn’t answer you directly, but should definitely put you in the right direction: Accessing Vertex Positions of static mesh - #2 by Rama
Long story short, you can retrieve the data you need from a specific LOD in your mesh by accessing the corresponding LODResource from your Mesh RenderData property (check for RenderData and search from there: UStaticMesh | Unreal Engine Documentation).
Hope that helps,
f