I don't have a 757 emergency checklist. but things are similiar with other boesing I'm sure.
I think you can "dump the cabin" (depressurise) to aid in smoke evacuation...of course at high altitude you would need oxygen masks.
if someone has the checklist, I hope they post it.
from 36000 to 10,000 takes about 5 or 6 minutes give or take.
the plane was near santa barbara, which has a 6000' runway, nearby 2 military airports with 15,000' and 11,000'.
I hope details come out.
I can just hear the captain to the chief pilot: in the sim, we always evacuate via the slides!