after you boot with the Fedora DVD and do the chroot to /mnt/sysimage and running the grub2-mkconfig, did you run a grub2-install? That is what actually writes the bootloader code to the boot sector
Boot again with the DVD and go to the chroot again, then
grub2-install --force --no-floppy /dev/sda
Looks like Skull One has faster fingers than I do.