I have not entirely ruled out any issues with the imposter material in the repro, there's a chance this is related to the normal rotations, but turning off distancefields entirely does fix the issue. See UDN entry for more details.
Download the licensee repro here - [Link Removed]
Go to IssueExample.umap (may be hidden behind the Show Developers Content flag in content view options).
The LOD1 of the static mesh is a WPO influenced sprite, whilst LOD 0 is the regular static mesh.
If you zoom out, lighting is lost on the LOD1 imposter mesh.
Looking through renderdoc, the pass that shows the most obvious error is CombineCones where the DownsampledBentNormal appears to be skewed despite the SRVs seemingly looking legitimate.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-124586 in the post.