If you've already added bourbon to the brew, I wouldn't soak the oak in more. IMO, sanitize via a small hot water bath (use just enough to cover the cubes, then seal up). Especially since you're looking to gain OAK flavor in the batch. You can always add a shot of burbon if you want more of that flavor.
I'm getting more into kegging these days. I have the hardware coming to be able to bottle off the faucets too. With that, I'll be able to keg entire batches and bottle up a few as needed. IMO, far tighter control over carbonation this way. It only takes a couple of over carbonated bottles to see the benefit of using CO2 via a regulator for carbonating.