"Pete C." writes:

Someone parking a grill or a hibachi there would be very unlikely to
create the damage pattern seen. Heat from either would be almost
entirely radiant. Based on the 4" wide outlet in the photo, a grill
parked in that location would have damaged the siding almost all the way
over to the door, and would not have caused damage to the siding that
continues past the railing as it clearly does. Radiant heat from a
hibachi also would not have caused damage continuing past the railing.

Yep, you keep saying that. But it looks exactly like what I would
expect a grill to do.

Not so much heat near the bottom, a lot right where the grill bottom
and lid met (even with the top of the railing) and a deflection
where the heat rose from the grill and was carried by a breeze.
That might explain why the melt isn't a bit wider.
If that plate is 4 inches the melt is about 9 inches.
I'd guess the grill depth at at least 12 but the melt pattern
would be a bit narrower and could be deflected a bit by a breeze.

Then there is the issue of the light and door.
Why would someone move the grill there?
Do see in the dark and to stand out of the rain.

Anyway, these are all guesses, no need to call anyone a moron.