I think you times are written wrong.
The cruise leaves from LAX at 16:00 which is 4pm.
The flights you have said arrive at LAX at either 10:40 which is in the morning. The otherf light you show is at 06:20 which is even earlier than the 10:40 flight.
Whatever you do you will need to have checked in for the cruise 2 hours before departure.
Many times you can start checking in for the cruise after 11 am. Keep the 10:40 flight. By the time you get luggage and to the dock you will be able to check in for the cruise. You might not get into your cabin but they will take your luggage and have one of the decks open. They will be serving lunch. Hang out on the deck drinking till it's time to sail away.