@comlys I just tested your suggestion regarding switching the shading model from Thin Translucent to default lit/translucent, and visually it seems to fix the issue, however I think that’s just due to the strong reflections not being visible anymore. The issue with the mirror reflections still persists.
That being said, i’m not sure if these are two unrelated issues or not.
I’ll see if I can separate the window into two separate pieces and use thin translucent to see if that fixes the issue
UPDATE: I imported the glass as two separate geometries in conjunction with thin translucent and am still getting reflection glitches. Is my geomtry not set up currectly by chance? I just selected one side of the glass and split it into its own mesh (they are individual static meshes in the cars BP).