$100 Strange Error?

Photo Shop.
Bill Collector

Is it really genuine?

I cannot imagine the way how this error could have occurred at the BEP, this is the very reason why I have posted it.
The note is real but well circulated so obviously one cannot rule out that it wasn´t tampered with. But by fake you want to say that somebody has erased the right serial number and somehow "projected" the squeezed one on the note?

Notice how the numbers appear faded at the top where they should be.

Such an effect might have been created if the note were placed upside-down on its side in a shallow bucket of solvent. The solvent soaked up through the note by capillary action ("down" when the note is turned right way up again), carrying the ink with it. The note was taken out of the bucket of solvent just after the solvent line had passed the serial number. If the note had remained in the solvent for much longer, it would have carried all the green ink, from both serial numbers and the seal, all the way down to the bottom of the note.

I can't see such a bizarre set of circumstances happening by accident - if a banknote is going to randomly fall into vat of solvent, it will likely fall in completely (and thus all the green ink would be completely gone), rather than balance itself precariously on its side. So I would conclude that someone deliberately concocted it as an "error" by carefully placing this note in that situation.