It took them 20 years to make enough juice to fire-up the ship. In the dialogue between Christopher Prawnpants and the "lab" prawn they mentioned it had taken twenty years to produce the stuff one drop at a time.

Vikus was a boob because he was in way over his head. He was given the surprise promotion because dear father-in-law wanted to engineer the outcome. If Wickus failed then MNU contractors can step in guns ablazin' and "clean up" the mess and reduce the number of prawn that needed to be moved. If Wickus succeeds, then…