Based on this, the second reason is because the Vorlons are one of the wisest and ancient race of the universe and thus, they are helpful as diplomats between younger races.
What? No. That's not how the Vorlons worked at all.
Also, Javascript is basically the Shadows (mordon.js lol).
Wonder what langauges/frameworks map onto other Babylon 5 concepts?
Angular -> Earth Alliance? Enterprisey but not super elegant, and collapsing under its own weight and propaganda?