In table 7-5 in the iOS Human Interface Guidelines, the italicised 'i' icon is included. The table is labeled "Standard buttons for use in table rows and other UI elements".
Opposite the icon within the table it states: "Flip to the back of the view to display configuration options or more information. Note that the Info button is also available as a light-colored “i” in a dark circle."
Does this mean that this or a similar icon cannot be used for anything but configuration options?
On
Apple of course will be fine with anything along the guidelines you quote. If you start to stray too far from the function of presenting information, then yes, Apple will reject.
Do you have something else in mind for the icon?
Update: In the situation you describe below, I think the info icon is perfect. Especially considering that you intend to closely affiliate the icon visually with its subject - your manuscript.
I've seen this icon used for many things, such as indicating there is more information to be seen, to information about the app itself that have been approved, so no the icon can be used for other things outside of configuration options.