PIE/PIF scans only have a limited value, they are not the end-all, be-all of quality. To understand disc quality, you have to run a battery of varied tests on a large enough sample size.
People get a variance in scan from one time to the next, and they want to scream bloody murder that the disc is dying when that is actually one of the least likely problems.
Changes in the drive and variances in the scans are far more likely than a disc falling apart in front of your eyes. Discs were made to stand the test of time, decades, sadly players and burners were not. Discs outlive laser readers/writers, happens all the time.
If your disc here is fake, and "suddenly" does not scan right, it's more likely that your first scan was faulty. Fake media is never that good, most of it is quite pathetic. Just be more careful in the future.