Email EA if you want a code and tell them about your struggles. It took them about two hours to send me the email.
I sent EA an email from the EA help page. I noted that I hadn't received a beta code and that I was tired of trying to jump through hoops on twitter. They then sent me the following email....
Greetings,
Thank you for contacting us with your Titanfall Closed Beta code concerns. We are happy to let you know that we are able to replace your code. Please note that the following code is redeemable for the Xbox One only.
Titanfall Closed Beta key: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
We tremendously appreciate your support and hope you enjoy the Beta.
Prepare for Titanfall!
Sincerely,
EA help