“I think it’s a great hoax…”
The entire issue of “segulahs” and their legitimacy is a really grey area in our hashkafah with some holding strongly by certain segulahs associated with very narrow and specific actions (i.e. being machmir on a certain mitzvah at a certain time/location) or more generally “buying a segulah” by giving tzadakah to a Rav/Mosdos to daven on your behalf for one/multiple segulahs, sometimes linked to a yahrtzeit at the kever of a big tzadik. There are frequent ads on all the frum media an websites promoting various segulahs linked to financial donations.
Bottom line is that some segulahs appear to have strong foundations simply based on their “sponsorship” whereas others appear borderline new age kefirah. I guess its all based on the emunah of whoever is seeking the segulah, the credibility of the sponsorship and their willingness to pay.