Variable being interpreted as a command in a bash script

Hello,

I have a bash script to do some security tasks for new Ubuntu or Red Hat based servers.

As one of the steps, if epel isn't supported, I add it to facilitate installation of fail2ban.

I collect the information needed and store it in variables:

# Determine architecture and store in "arch" variable
arch=$( /bin/arch );
# Determine major release and store in "release" variable
osRelease=$( cat /etc/*os-release | grep PRETTY_NAME | cut -d " " -f 5 | cut -d "." -f 1 );

I then use the variables in a command to support epel:

sudo "subscription-manager repos --enable codeready-builder-for-rhel-"$(osRelease)"-"$(arch)"-rpms"

When the command runs, the place where osRelease should be is empty and when it runs, I get an osRelease: command not found error when it reaches that line in the script:

./first-ten.sh: line 337: release: command not found
Error: 'codeready-builder-for-rhel--x86_64-rpms' does not match a valid repository ID. Use "subscription-manager repos --list" to see valid repositories.

Note that the number 9 should be between the hyphens between rhel and x86_64, but it is empty.

When I run echo $osRelease, I get the number 9, which is correct.

I believe I'm missing something simple but have not been able to figure it out yet. Any insight is much appreciated!

Full script is available on github here: https://github.com/TedLeRoy/first-ten-seconds-redhat-ubuntu/blob/master/first-ten.sh

Any thoughts on script improvements are most welcome too.

Thanks!