I'm no expert, but one of them, the non yellow poly doesn't quite look an ornate. Shouldnt be the problem though. Can try the driftwood maybe.
I personally would be cautious in general with introducing a lower jaw with small upper jaws. Out of all the laps and lap variants I have none have shown any noticeable aggression. If I were you I would try and bulk the ornates up as much as possible, otherwise the lap may see them as a possible food target. IME though laps seems to be very laid back and if kept well fed should be fine. I would just be cautious and make sure everyone is kept well fed.