You may try to use the following command-line method to find out your Apache group names:
WWW_GROUP=`ps axo user,group,comm | egrep '(apache|httpd)' | grep -v ^root | uniq | cut -d\ -f 2`2| uniq`
echo Apache group is: $WWW_GROUP
To get the user, check: How to determine Apache user from the command-line?