If someone were to intentionally publish indexes that associate pirate titles with non-pirate SHAs, I imagine they’d be able to cause a lot of trouble for the DMCA takedown industry.
Who knows, maybe that's exactly what happened here. Could be a vigilante trolling the copyright trolls. (Not all copyright firms are necessarily trolls. The ones that recklessly automate things so heavily that they'd make this mistake probably are, though.)