Apple seems to be rejecting the app using the 6.7.11 version of the library. The user defaults key is wrong, it should be User Defaults instead of UserDefaults
Here is the rejection description i have received:
ITMS-91054: Invalid API category declaration - The PrivacyInfo.xcprivacy for the “Frameworks/YouboraLib.framework/YouboraLib” file contains “UserDefaults” as the value for a NSPrivacyAccessedAPIType key, which is invalid. Values for NSPrivacyAccessedAPIType keys in any privacy manifest must be valid API categories