MDMA oil is crude freebase MDMA.
Quite why law enforcement like to make this distinction is baffling. I think it has something to do with US/AUS retarded obsession with crystal this and crystal that, as being something special.
.
Australia and the US are completely different countries and very much so in drug terms ect
I don't see anything weird about saying 750kg in crystalline form and 517L in oil?
Its completely relevant to the article, as it was going to be imported too Australia. Being solid/liquid plays an effect in importation methods.