Well said.
I would also submit that this mysterious sudden application of
throttle is likely only reported in cars with automatic transmissions,
since the resultant crash would probably be avoided if one foot was on
the clutch--i.e. the person backing up (in this case) and experiencing a
sudden racing of the engine would instinctively stomp the clutch and get
the vehicle stopped, perhaps more slowly since some of the pressure is
on the throttle as well as of the brake...you get the idea.

Then the driver would look down and realize what was happening, and
take their foot off the accelerator, hence there'd be no accident to
leave them all dazed, confused, and fully convinced that the "engine
just raced unexpectedly" --since after an ordeal like that many people
are often somewhat traumatized and don't really have a clear idea what
the hell just happened.
Just my 2=E7.

BTW I'm new to this forum, very interesting & informative.