You shouldn't need to pitch any sacch now. At standard ale temps, it's the fastest thing in the mix. Adding more sacch will make for less lactic acid production by the bacteria, which is fine if that's what you want. These blends do get more sour with every subsequent batch, so adding a little sacch to the second batch is not a bad idea, unless you want it more sour then the first. I don't think people use the same cake repeatedly, but you can certainly harvest and pitch like you would for clean beers. You shouldn't need to use any oak if White Labs doesn't.
Say no to intolerance: love gluten and lactose.