I've managed to cobble together a few good lines so far. I've been able to create several decent-sounding lines from frankensteining together bits from Batman Begins and TPM. I'm thinking of how to craft a conversation with Yoda using existing dialogue.

I still want Liam saying "Run, Yoda. Run." I'll settle for "Run." This would be the first we hear of his voice.

As Yoda watches the cloak fall, we hear

Qui-Gon: "Run, Yoda, Run. Run, or you will be discovered."

(later, as Yoda is crawling through the crawlspace, we hear his thoughts as he talks with Qui Gon.)
[from this point forward, I've assembled Qui-Gon's dialogue. I have his lines all ready to go.]

Qui-Gon: "Do you feel responsible? Finding him was the will of the Force. I have no doubt of that."

Yoda: "Failed I have."

Qui-Gon: Sith Lords will not share your compassion. If you let it, it will destroy you, as it almost did me."

pause

Qui-Gon: "My master, you must journey -- for your own sake."

Yoda: Into exile I must go.

"You must, my Master. There is no turning back. May the Force Be With You."

Then clip those lines when he's rescued by Bail. They fly off silently instead..