Yes, I fear that ISOBuster was my wrong recommendation, but I'll let the Puzzle experts come back and hopefully give you good guidance at this point. I'll keep watching for this, too - it's an inevitable occurrence for all of us.
Oh, something else to consider - do you have easy access to other computers? If there's a need to let it "run forever", having an old, back-office slow-boat-to-China PC might be 'just as fast' and maybe could be left to run for days or ??
In addition, maybe older drives might yield a different result (as if newest drives are now more overloaded with pure genuine plastic instead of metal).