Is @Sophie able to help here?
Sounds like a bug. Please submit a ticket through the form at the bottom of www.funimation.com/contact-us. Be sure to mention that the data below the player says "1080p" while the player only offers 480p.
That could also be an indicator that the resolution displayed there is for the show as a whole and not for that specific video, which would be another bug.
I actually asked this question late last year when the Blu-ray came out and this was the response I got:
Thank you for contacting Funimation Support. We are happy to hear you are a fan of "Ergo Proxy," it's a great series!
Typically with the home release of a title, the corresponding episodes will become available for streaming shortly after the release. However, at this time, the upgraded versions of these dubbed episodes are not available. We do not have a timeline for when they'll be added, please keep checking back at our website for further updates.
If you have any other questions, please let us know.