The problem with inaccuracy in poems/lyrics is that you are painting a scenario, and once an inaccuracy is spotted it looms much larger than the odd word or two that describe it.

Longfellow wrote about King Arthur and castles with sunlight streaming through (large) stained glass windows. In those days glass was expensive and windows in castles were small for the safety the castle provided. It is possible that a king could afford whatever he wanted, but................

Knowing there is a wrong fact has already conflicted you. I would try and change it. It is always possible to change the word order, the English language is the one medium that affords such richness.

GBS said "the golden rule is that there are no golden rules" - but you have to carry the audience with you for that to be true in this context.