Cevah is exactly right.
Crafting and Bypassing Requirements: What crafting requirements can you bypass by adding +5 to the DC of your Spellcraft check?
As presented on page 549 of the Core Rulebook, there are no limitations other than (1) you have to have the item creation feat, and (2) you cannot create potions, spell-trigger, or spell-completion magic items without meeting their spell prerequisites. So racial requirements, specific spell requirements, math requirements (such as "caster level must be at least three times the enhancement bonus"), and so on, are all subject to the +5 DC rule.
The text in the CRB about having to know the spell requirements is poorly worded.