Change SQL Server 2008 name
If you aren't changing the physical server's name you'll need to change the name that SQL Server knows back.

sp_dropserver 'SERVER2\SQLSERVER'
sp_addserver 'SERVER1\SQLSERVER', local


You then just need to put an alias in DNS so that when people try to connect to SERVER2 then are redirected to SERVER1 without knowing about it.  Specifically you'll want (or you'll want your sysadmin) to put a CNAME record into DNS pointing SERVER2 to SERVER1.