Conspiracy!

[Kampanom]

Amazing, you managed to be right for all the wrong reasons possible.

In as far as the Noms need humanity, you're right, but the entire thought process to come to that conclusion is pointlessly complex and wrong.
I will quote from Chris Todd's design document to give you a better idea of how or why the Noms require humanity. though I still haven't figured out if any of the Nom factions stick to this plan in Disco:

In the process the Nomads learned quite a bit about humanity and began to understand how we had appropriated the knowledge that the Daam-K'Vosh had intended for them. They also realized that our own civilization was technologically more advanced than their own -- but much as humanity had taken the remnants of the Daam-K'Vosh civilization and made it their own, so the Nomads decided that they would take our civilization and rebuild it in their own image. We had already unlocked secrets of the Daam-K'Vosh that it would have taken them millennia to uncover. Besides, human bodies were warm, their senses exquisite, and they reproduced so quickly as to make any one body expendable. The Nomads thought that, yes, they could grow quite accustomed to making their homes inside of us...

then

But as they learned more about us and our politics, they realized that they wouldn't need to fight us: we would do all the fighting for them. All they had to do was apply pressure in a few critical places and humans would surrender to their natural violent instincts. Once we had expended ourselves in a futile fight waged against phantom aggressors, the Nomads would easily be able to assume control and use humans as a vehicle to expand throughout the galaxy

tl;dr, we aren't needed merely to build them a fleet, we're needed mind, body and soul. Everything of humanity is needed, the species itself for the comfortable bodies it can provide (one, I'd argue, even physically closer to the Daam K'vosh. They had writing, hence hands, hence opposable thumbs, hence... you get it. What if there's even an emotional component in trying to look like Dad?), and its culture and technological advancement because it's inherited from Dad what was supposed to go to them.
The wars they provoke, ways to reduce the human population to a more manageable size, one that allows them to take us over in every meaning of the word.

I don't know if the Nom factions in Disco have this (unachievable) plan as their long term objective, but if they do, for all intents and purposes the future is Wild according to them.