I was rewatching RvB Episode 100- Why Were We Here? and noticed a line that seemed really familiar.
It seems really close to a popular line re: the lunar point of origin of a certain 3rd tier Hive enemy that was in the Alpha but was replaced during the Beta.
Video is here @ ~7:50 : http://roosterteeth.com/archive/?id=261&v=more&s=5
Transcript of the episode http://rvb.wikia.com/wiki/Why_Were_We_Here%3F
Maybe this is why it was removed as someone else noticed it and they had to replace it.
Or maybe just the beta build was updated with alternate audio until they could finish remastering the original from the alpha for the final release.