Could be, Roberto, but proving the negative is always tricky. :)

BTW, one way I heard this song, it started with a numerical build-up through the first three verses:

There's one kind favor I'd ask of you ....
There's two white horses in a line ....

There's three black coaches by the road [x3]
Empty, empty now of their heavy load.

[I.e., the coffin and the mourners have dismounted at the grave site.]

The way I was taught it first was

Got six white horses followin' me... [x3]
Gonna lead, gonna lead me to my buryin' ground.

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