I'm too having this problem, yet I decide to del the plugin through the ftp, but when I reupload again still getting banned, 403 forbidden.
Then, I go to phpmyadmin and del the 18 table of wf, problem solve for a while then getting banned again, I repeatedly change and edit my htaccess with the default rewrite rule from codex, when getting banned again, I edit back, edit and edit htaccess with the default rewrite rule.
So then I feel tired and stupid, I decide to deactivated my hide my wp plugin, install Wordfence from plugin installer (because when I del the table, the setting and api key won't show and stick when install through plugin installer it's working).
And ...
My site gone alive and no more Forbidden Error 403 with:
Del all Wordfence Database Table.
Del Wordfence folder through ftp.
Deactivate any plugin that hide wordpress file.
Install Wordfence through plugin installer.
Setting the falcon Engine.
Then I'm deleting my entire all off my browser cookies and cache (Opera, Chrome, Ie11, Mozilla, Aurora).
Zaaappp.. My site are alive, yeayyy!!! Running with God of Speed Falcon Engine.
So for final solution to all, I suggest to you del your entire cookies, especially the browser that you are using to login to your wordpress site. And the most problemtrouble browser are Google Chrome!!!
please mark this topic solve.