Second, I think Johnny nailed the other part. They've got 40 episodes of 100 done. A regular TV series runs 22 to 23 episodes per season. That puts this cartoon at two seasons of material ready to go already, but they probably want a 5 year commitment (100 episodes) from the network. No network is going to do that, even if a show does look good. You can come in with a 5 year plan, but if they decide to cancel you in the first season or even after a few seasons, you better be able to wrap things up or get ready to send it straight to DVD.
I know of only 3 shows (well, maybe 2) that had a 5 year plan at the beginning and all of them ended up running longer. Babylon 5, which the network made a mess of by constantly playing the "you're cancelled...well, no you're not" game, X-Files, which Fox pushed 3 years beyond what Carter ever intended (and it shows), and Buffy the Vampire Slayer, which didn't turn out that bad (there's even a Season 8 comic

I'm almost hoping this does fail to find a network. Then they'll be forced to release it on DVD. I really doubt we'll end up with an LFL network. What would they air? LFL movies and news 24/7? There's only so much of that I can take these days (about once a week is plenty).