I decided to try out LHDR. Used all the defaults and applied auto anti-ghosting. I get this throughout the image (sample brightened)
PS It couldn’t detect the EV, so I copied that from HDRMerge. Maybe that was my undoing.
@afre please file bug reports in GitHub along with the needed basic info (version, samples, etc.)
http://rawpedia.rawtherapee.com/How_to_write_useful_bug_reports
@gaaned92 You might be interested in this. (Maybe update Luminance HDR and HDRMerge. 
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