Artefacting between meshes using the same translucent glass material

The front glass and back glass are two separate skeletal mesh components.
The artefacts appear on the component that is behind the first component.

I got these glass materials off the marketplace.

This is the material instance:

This is the base material:

Any help solving this please?

PS: The flickering artefact on the seams of the two components are not caused by overlapping faces, there is indeed a gap between them.