Facebook – Add Administrators to a Facebook app if only Developer role is filled

You can only send event invitations to friends and group members, not to everyone that likes your page. However, you can post the event on your page, so that it will appear in the News Feed of people that like your page. The post will have a Join link for them to RSVP to the event. If you want more exposure than that there is also the option of purchasing a Facebook ad for the event, in which case numerous targeting options are available (including the ability to target only people that like your page, or friends of those people, or everyone within 50 miles of your city with a certain interest, etc.).

All you need is this form and all you need to be is patient and vigorous and in the end you even get an eMail response from an actual human begin.