Whoops, that was the same order you had read - KHOU’s site wasn’t coming up for me when I looked, but it’s back now.
There are a few possibilities I guess.
1- Worst case scenario- mass casualities.
2- Because the damage is SO extensive out there- they have decided it is truly unsafe for anyone to try to go back and will result in more emergency rescues being necessary- tying up busy SAR crews for no good reason.
3- Communication is confused and even the officials/authorities are in shock- resulting in weird behavior by everyone.
I can’t think of other reasons- but I’m probably missing something(s).