I did consider that; however, the text was originally hand-written by someone who was adept not only at Tibetan penmanship, but the kind of punctuation marks that go along with mantras, and in this case the specific markings for a terma, as pemachopel pointed out. On top of that, they used the very specific, more complex kind of Tibetan spelling that marks Sanskrit-origin texts as opposed to native Tibetan texts.
Really the only thing for me (and maybe this just reflects my own ignorance) is that the words themselves are very unusual. "Pranking" a mantra (unless they wanted to do it to bring bad luck to the Chinese pendant-seller lol) doesn't seem like a very karma-forward move; so I'm more inclined to think it was purposeful.
I just have to think that the overabundance of "b" gives a clue; there's even a "b" incorporated oddly into the initial "aum" syllable:
This next syllable, as a possible crypto-spelling of "bod," also jumped out as odd--it looks as if someone has added extra elements (or put them there in the first place), and once again, we have a superfluous tiny "b."
Very intriguing - I continue to appreciate all thoughts on this!