I think things have changed. Currently it depends on the situation (if the application is in the US or not, visa type, other waivers needed, etc). In our case USCIS will adjudicate the waiver.
https://www.uscis.gov/forms/all-forms/direct-filing-addresses-for-form-i-212-application-for-permission-to-reapply-for-admission-into-the