Re-captcha 2 and keyboard accessibility

I have implemented Google Re-Captcha 2 on a login form for a website and am currently doing accessibility testing on it (particularly in regards to simulating the experience as a blind user). I find that although there is a "voice over" option to complete when challenged, I cannot seem to give focus to the modal window that pops up with my keyboard to launch the voice option. I thought this might be a problem with my site, but I have tried it with a plain HTML page, and get the same issue. I've looked online, and Google mentions that you can click the voice option (which you can), but I don't see the point of that if you are visually impaired (if I could see that small voice button, I could see the rest of the captcha). Does anyone know if this is an existing issue with Google Re-captcha 2? Is Google Re-Captcha 2 not supposed to be keyboard accessible? -- You received this message because you are subscribed to the Google Groups "reCAPTCHA" group. To unsubscribe from this group and stop receiving emails from it, send an email to recaptcha+unsubscribe@googlegroups.com. To post to this group, send email to recaptcha@googlegroups.com. Visit this group at http://bit.ly/1dkFnYd. For more options, visit http://bit.ly/P65DvS.