"Battle of Otterburn"

The event itself was real enough and can be found in both Scottish and English sources though they differ on what day of the month it was fought. Relatively small Scottish attack on Newcastle area in 1388 leads to English pursuit which catches up with Scots at Otterburn where James Douglas,2nd Earl of Douglas, the Scottish leader is slain before the English are eventually pretty heavily defeated. On the face of it the main vein of the Battle of Otterburn seems more historically accurate and is quite different from Chevy Chase. Does the above ballad perhaps talk about the reason the Scots attacked and then the eventual battle without referring to the Scottish siege and retreat prior to the battle? Or is it perhaps talking about some other event - after all there were plenty of Douglases and Percies.