Wow, this is quite the thread revival, isn't it? Well, since it's here now I might as well throw my two cents in. Honestly I don't think there IS a real translation for it, and if there is the developers certainly aren't making it easy for us. But I think the answer to the meaning of "Kale watcha nei conserva oh!" isn't found in that particular sentence, but in the entire quote Joshua uses.
"You took advantage of us at New Canaan to drive us out, and like the dogs of Caesar you are, you followed us to Zion. And now you stand on holy ground, a temple to God's glory on earth. But the only use for an animal in the temple is sacrifice! Kale watcha nei conserva oh! You understand me, don't you? Don't you?"
Obviously Joshua is telling Salt-Upon-Wounds that he made a mistake following him to Zion, but if we look at the entire quote instead of just the word, than I don't think it would be far fetched to assume he was saying something along the lines of "And now you are a sacrifice to god." Given the context of what Graham says, it's in my humble opinion that what he said was probably along those lines.
Sadly, this is probably be one of those Fallout things we'll never actually find out.