E. D. Called BackAfter logging-off the night I made the epitaph entry a question nagged at me as I prepared for sleep, because it didn't make sense, somehow, that such a long poem would be inscribed as the epitaph on a tombstone. Indeed, my suspicions bear out. Upon further research I confirmed that
E. D. Called Back is the
complete text of the epitaph inscribed on her tombstone (and is NOT, therefore, the original title of
Because I Could Not Stop For Death):
In 1884, Emily became ill with a kidney disease generically called "Bright's
Disease," and soon became bedridden. She died after lapsing into a coma on
May 15, 1886. Her tombstone epitaph contains the two words she sent in a
message to her cousins shortly before she died: "Called Back." http://www.allsands.com/Literature/emilydickinson_akh_gn.htmThe wording of the site previously cited was misleading, and seemed to point to the other conclusion. (
two sources! 
)
The reference to an original text of the poem
Because I Could Not Stop For Death is correct and accurate.