The error:
"Permission Violation: You need the 'Custom Body Fields' permission to access this page. Please contact your account administrator."

normally comes from NetSuite directly. It means that the roles assigned to the OAuth app are likely different from the roles that are assigned to the user you are authenticating with.

In order to get around this, you would want to set the CustomFieldPermissions property (this can be set in addition to or instead of IncludeCustomFieldColumns).
Link to online documentation of CustomFieldPermissions available on our website:

https://cdn.cdata.com/help/DNH/odbc/RSBNetSuite_p_CustomFieldPermissions.htm 

This property can be used to specify which custom fields' metadata should be requested by the CData ODBC Driver for NetSuite. For example, to specify all of the custom field permissions for all available tables, set this to:

Custom Body Fields, Custom Column Fields, Custom Entity Fields, Custom Event Fields, Custom Item Fields, Item Number Fields, Other Custom Fields.