There is no way out. The only thing you can do is to post a response subsequently saying that you have updated your post with some additional information and request the members to take note of the same. Posting of responses cannot be helped even if you request an editor to do the needful because, by the time the editor intervenes, responses would have already been posted.
It may also be noted in this connection that members, other than editors, have not been given access to other options like locking etc in the total interest of the site.
'Mastering others is strength. Mastering yourself is true power'. -Lao Tzu