Being clear on what “inerrancy” means and does not mean would help. Here is a definition (italics mine):
Is the list of numbers of chariots and horsemen supposed to have exact, scientific precision? 83,712 horses?
Or did the author mean to give us an idea of how big is the army i.e. in approximations? 80,000 horses?
But if the purpose is to report it Jabatan Hasil Dalam Negeri, I'd have to be more exact!
Another question to consider: Is this to be interpreted metaphorically or literally?
Some numbers are symbolic like the number 14 in Matthew's genealogy.
Sometimes we speak of things as we see it. Like the sun will rise at 8 am. Now we know that actually the earth moves. But even scientists talk about sunrise regularly, they do not take it literally but as how they see it. It is not a scientific “error”.