On the top of the score it shows info about the lyrics top left and the tune top right. The tune is simply noted as "Scottish folk song" arranged by K. Lee Scott

That suggests that the name, if one ever existed for this tune, has been lost in the mists of time. Copyright convention dictates that if K. Lee Scott actually knew what the tune was called he SHOULD have used its proper name

Have you searched for information on the arranger? Such a search may throw more light on the subject