We all know we could argue all week about the definition of a ballad, but I think we can agree that one thing about ballads is that they were widespread. Real ballads in the sense of 'Child Ballads' are found in many versions in different places. Furthermore, they may be found to be of different ages.

I have read of ballads collected in England whose plots were retold as far away as Lithuania and Turkey.

That 'Judas' poem, now. I have studied Middle English, and rarely have I come across anything as obscure and nonsensical as that. I think that after it was written down, it stayed shut up in an old MS for centuries. Therefore, it's not a ballad. It never got to roam.