Premise:
"The original decoration has long since disappeared."
Hypothesis: The original decoration has been gone for a long time.

yes

Premise:
"too much credence given to incidents exposed elsewhere as hoaxes and illusions."
Hypothesis: So much praise for a magic trick that could be easily explained.

it is not possible to tell

Premise:
"Soon some spoke of not a warband cutting them down, but a single man."
Hypothesis: Soon people discussed a single man cutting them down, not a warband
yes