Need help, replacing back housing of g2 D800 topic

Hello all, recently got a g2 at&t d800, now want to change the back housing to golden or red color, saw some of them on ebay, but they don't have the hole for the extra microphone for D800, is that third microphone really important? Is there any use of it?, I am currently using cloudy g2
Also on many cases there is the same issue, they don't have hole for the extra mic on d800.
Any help would be really appreciated
Thanks in advance