I would get them out of there.
I was on the phone immediately to them for the third time today, spoke to my Teutonic-skulled father and said, Cat 5, GET OUT! The error margin is just too low - they were off by 15 miles with Katrina's eventual landfall this far out, and for them that's the difference between Cat 2 and the west eyewall at high Cat 3. And if it's off 50 miles, it goes right over them.
He's packing now. They'll make a final decision tomorrow, but at least they are getting ready now.