[CentOS] grubby fatal error: unable to find a suitable template

I did a bulk "yum update -y" of several servers.  As a sanity check
after the upgrade, I ran a grep of /etc/grub.conf across all updated
servers looking to ensure the kernel I expected was installed.

Two servers came up saying /etc/grub.conf did not exist!

I logged into the servers, and /etc/grub.conf was a broken link.  (It
points to /boot/grub/grub.conf).  My systems are all setup with a
dedicated /boot partition.  Sure enough, /boot was not mounted.
Furthermore, I saw no /boot entry in /etc/fstab (which all my other
servers contain).

So I mounted /boot, and the the grub.conf file was not consistent: it
did not have a stanza for the kernel I wanted installed.  So I did a
"yum remove kernel ; yum install -y kernel".  Both the remove and the
install resulted in this message getting printed:

grubby fatal error: unable to find a suitable template

Just for kicks, I renamed both the /etc/grub.conf symlink as well as
the actual /boot/grub/grub.conf file, and repeated the kernel
remove/install.  This did NOT produce the above error; however, no
symlink or actual grub.conf file was created.

I did a little web searching on the above error, and one common cause
is that there is no valid "title..." stanza in the grub.conf file for
grubby to use as a template.  But my file does in fact contain a valid
stanza.

I even copied a valid grub.conf file from another server, and re-ran
the kernel remove/install: same error.

Clearly, something is broken, but I'm not sure what.  Anyone seen
anything like this?

By the way, these machines were all 5.something, being upgraded to 5.7.

Thanks!