I will enter His gates

Is this truly a traditional tune that Harper Collins Religious had a right to copyright an arrangement of, or is it really the same tune as this, that is a tune composed by one Leona von Brethorst and copyrighted by Maranatha, or is the latter actually just Ms. von Brethorst's arrangement of a traditional tune? The hymnal I am working on (LW1978) credits the tune to "Mrs. Leona Von Brethorst" and says "Used by Permission", but doesn't give copyright info nor say whose permission it is used by...

I would like to combine the two tune authorities, but would like to know that they are the same tune, and who should be credited, before merging them. And yes, I know this should actually be in the Editors forum...