With separate tickets you are (almost) always never protected.
With the same carriers, you stand some chance of better assistance, since the next flight's carrier is the same as the one you just disembarked (and also made clear at the start of the journey). In addition, since this is OZ's home base, a little bit more comforting in that regard. Checking through your luggage helps a little bit, but only if your connection becomes tight (i.e. there's still time to rush your luggage from one flight to the other), not if you miss it completely.
Between that known and the service factor in Korea (similar to Japan in a way), you will likely be reaccommodated on the next OZ flight (possibly an alternative option and/or with overnight accommodation) if you do miss it due to a delay of the first one. They may get sketchy if you are on separate tickets (because the system will not show you as a passenger who was on a delayed flight, but rather one who has missed a flight completely), but if you are humble and polite you should be OK.
If you have a > 3 hour margin I'd be pretty comfortable giving that a go. At LAX keep monitoring your departure time and if it starts to get closer to a possible misconnect (albeit significant delay by that time), start thinking about talking to the OZ service counter.