I know a third verse, besides the two in DT:
Wrap him up in a silken shroud(3x)
It was Willie, what got drownded in the deep blue sea.
but it sure seems like there should be more.

Also, can anyone tell me where this comes from?

I sang it last week, and one of the folks, unfamiliar with it, (is this possible?) thought I was singing "What GOD drownded..."
Blessings,
Barbara