Single Surface has internal edges

Hello all,

I’ve got a surface and found it has strange internal edges (see image shown below).
I want to clean it up so that a clean boundary can be generated.
Here’s what I have thought about and tried:

  1. Merge Faces - didn’t help since the geometry only has one face.
  2. Curve/Self - was thinking to use crvs mid points and cull the ones that are in side the surface, fail.

Any help would be appreciated!

Surface internal (1.6 MB)

Here’s an original version with all surfaces that need to be cleaned up … and hope to maintain tree structure …

Surface internal (1.6 MB)