In your circumstances Rita I would definitely let the cruise Line arrange your air. Hopefully you are using a living, breathing, around the corner Travel Agent or booking directly with HAL.
It is possible to make that 10.45 am flight but it's a risk and I'd not bank on it. As has been said there are to many things totally outwith your control. Cancellation, delay insurance is a necessity in your case.
I'd sure hate to go to night shift hours directly from a cruise - you're more than likely to 'fall asleep at the switch' around 4 a.m. your time. Think this through carefully before you make any commitments.
Fingers crossed that everything works out for you.