This message comes from the WrongDigest exception. It appears to me that this is being thrown because your download is legitimately (and repeatedly?) corrupted. Is there a proxy messing with your download or something?
Here's the code path for checking for corrupted downloads:
getShouldDownload -- calls
fileMatchesExpectations -- calls (and catches WrongDigest :: VerifiedDownloadException)
hashChecksToZipSink -- calls
sinkCheckHash -- throws WrongDigest
I don't think the exception is being printed out from this code path, because on this code path the WrongDigest exception is caught rather than being allowed to propagate to the top.
(I've manually downloaded the file in question and can confirm that it has the expected sha512.)
Here's a test case that claims to demonstrate that an existing incorrect file will be replaced with the correct downloaded file: