Not the same exactly, but the lesson is similar - follow the links when adding sources.
I recently was notified that Gedcom import was merged into a profile I manage. It included new and/or different information. The source cited for the information was an Ancestry link, which ended up being a link to Find A Grave. The Find A Grave memorial states: "There is no stone for this memorial. I have put [profile subject] here because his wife is here. Hopefully some family member will hunt for courthouse records to finally put [him] to rest where he belongs. The Find A Grave Memorial for the wife states, with respect to the husband/profile subject: [His] date of death and burial location are unknown. There was a deed for a sale of property in Schuyler County, dated April 25, 1874. That date has been copied over and over again as his date of death. No marker has been found for [him] at Wesley Chapel Cemetery; no will or probate file has been found in Pike, Schuyler or McDonough County.
So there really is no source. I added explanation and uncertainty markers.