Wow that looks hard to debug 
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While the artifacts look very similar, I believe we’re facing different issues. Since mine only happens when moving in front of the light source.
Also, when I set the visibility of that very bright flashlight to false (And increase the sky light), the trail is no longer visible either. So I highly doubt that the issue that I am encountering is related to the meshes themselves.
Yours, on the other hand, given the lighting circumstances, seems like might have a different cause.