It seems there may be something to Gilbert's story (although without any indication as to what subsequently happened to Luray and Carey) - at least the FBI seem to have thought so. A clipping from the Daily Independent from Kannapolis NC can be found at
The Daily Independent from Kannapolis, North Carolina on January 5, 1966 · Page 18 and can be read by clicking on OCR text. It can more easily be read in the attached picture (which comes from an unapproved site hence me not linking to it but it is a pic of the original clipping). It is a report of an FBI notice seeking Carey as a bail jumper and noting that,
"Carey may be accompanied by .......a 16 year old runaway girl."