The version I know is from the Creel's album Appellation (one of my all-time favourite recordings). It's very similar to the one in the DT here, but the villain is the stepmother. The liner notes describe the Lord Randall tradition as "the ritual of pre-Christian ... king sacrifice is acted out in the poisoning of the lord of the castle".
The lyrics of their version (with 2nd and subsequent verses cut down) are:
Where have you been all the day
Me own dear darling boy?
Where have you been all the day
Me own dear comfort and joy?
I have been to my step-mother
Make my bed mummy do
Make my bed mummy do
What did she give you for your supper?
I got fish and I got bread.
Where did she get the fish that she gave you?
Hedges sought 'em and ditches caught 'em.
What did you do with your fish bones?
I gave them to my greyhounds.
Tell me what did your greyhounds do?
There they swelled and there they died.
I fear that she does you a deadly wrong.
She took me in and did me slay.
What will you leave all to your mother?
I leave her me house and me land.
Tell me what will you leave your step-mother?
Buy her rope and there let her hang
by a halter that hangs on yon tree
for the poisoning of me
Cheers Chicky