Authors versus Characters

I've just finished reading The Almond Tree by Michelle Cohen Corasanti  (It's important to give the author's name here.  Three books with that title can be found in Kindle Store.) This one is a novel set in Israel,  an historical saga spanning 54 years ending in 2009.
Strong threads of determination, optimism and family values run through the  narrative consisting for the most part of only too believable tragedies that beset the rural Arab-Israeli family at the heart of the story.
I found the story gripping and was impressed by its historical accuracy.
However, I have one query which is relevant not only to this novel but to many others where the action is seen through the eyes of a single protagonist and there is no author narrative.
A character in the novel  passes on information which he/she believe to be true and which supports the main thesis of the novel, yet  nowhere in the book is the misinformation denied so the reader is left with the impression that the falsehood is historically accurate.
Here is an instance. The children are listening to nostalgic conversations between their uncle and their father, I quote,
'From these talks, Abbas and I learned how in the nineteenth century Palestinians developed the Shamouti orange, also known as the Jaffa orange.'
The political importance of this statement is that both Arabs and Jews claim to have bred the Jaffa which proved to be a major element of  19^th and 20^th century prosperity in Palestine and use it to assert their right to the land.
In historical fact the Jaffa orange was developed neither by Palestinian Arabs nor by Palestinian Jews but by Germans or more strictly, as the reunification of Germany had not then taken place,  by a group of Christian Westphalians who sold their surplus nursery stock to fellow citrus growers, both Arab and Jewish.  All three grew rich on the export trade the Jaffa orange provided.
Now, I believe it is quite legitimate for an author to allow a character whether deliberately, or in this case unwittingly, to pass on unreliable information.  My query-  is it legitimate, in an historical novel for the author to allow that information to go unchallenged?

King Richard 3 The making of a website.

I guess by now that most people have heard that the bones discovered in GreyFriars,  Leicester have been confirmed as those of King Richard of Leicester, whose body, after he died at the battle of Bosworth,  was publicly displayed at the High Cross Street Butter market before Henry 7th buried him in a modest tomb  in the  grounds of Greyfriars monastery.
For centuries legend had it that when Henry 8th dissolved Greyfriars monastery, the people of Leicester so hated the memory of Richard 3rd that they rushed onto the site, demolished his tomb and threw his bones into the nearby River Soar.
There was even a plaque erected on a bridge to mark the site from which the bones had been thrown.
Many years ago, as an enthusiastic young junior teacher I had the task of teaching The Tudors to Standard 3.  The junior school history syllabus in those days went chronologically from Dinosaurs in Standard 1(seven year olds) to WW1 in Standard 4 (eleven year olds).
I decided to liven up the syllabus with local primary sources and local legends.
I went to the County Records Office (then housed near Victoria Park) and read an (as far as I can remember) uncatalogued letter from Christopher Wren , father to the famous architect of St Pauls, mentioning he had visited Robert Herrick, uncle to the famous poet and brother to the first of eight  William Herricks of Beaumanor Hall, and been shown the intact tomb of Richard 3rd in the garden of his house that had been built on the Greyfriars site.
I also found a copy of the penny ballad printed after the 17th century murder of the Innkeeper's wife of the Blue Boar Inn while she slept in the bed King Richard had left behind before marching on to the Battle of Bosworth.  The ballad linked the murder to the Leicestershire legend of 'Black Anis' (not to be confused with another Leicestershire legend  'Black Anna') and also to a cache of  gold coins the innkeeper's wife had found in the bed.
From this I cobbled together a serial story that  solved discipline problems for the last half hour of each school day.  It also enabled the class and I to escape the claustrophobic classroom on several occasions ,  while we explored on foot sites in the city associated with King Richard.  Twice we even went on  coach trips, once to Bosworth  (it didn't have a posh visitors' centre then so it was very much a DIY affair) and once to the delightful Donnington-le-Heath museum.
Twelve years ago, about a decade after I had retired, I created a website about King Richard and his Bed. Linear was even more OUT  then  than it is today. Countless links between pages  (there must have been over  100)  left the luckless reader drifting between dinosaurs, Cain and Abel the Vikings, Druids, Houghton on the Hill, Cheapside, Bow Bridge, Beaumanor, the Blue Boar, Bosworth and Donnington-le Heath to mention just a few.
Websites are like the electric cables that attach devices to one's computer.  Left neglected  they come adrift and tangle themselves up into fiendish puzzles.
When I resuscitated this website a week or so ago, it was completely unusable. I stripped it down ruthlessly - gone is the walking tour of Leicester - (during the past decade the council has demolished half the items on it). Gone is the history of the Herricks both in Leicestershire and America. Gone is the trail of  evil from amoebas to Idi Amin. Gone are javascript and frames. The site is now unashamedly linear, simply,  if old fashionably, coded and has only 19 pages. On my computer all  forward links work and all the images come up, although I haven't yet tested the backward links, so if you try it - keep going forward!  Here is the link.
http://landofbrokenpromises.co.uk/kingdickan/