I am guessing that somebody ran pip install requests on this system, and it's taking precedence over the python2-requests package, which is breaking Certbot.
FWIW we recommend using the Certbot snap to avoid these kinds of issues.
I am guessing that you are going to need to do something like:
sudo pip uninstall requests urllib3
sudo yum -y reinstall python-chardet python-requests python-urllib3
but be forewarned, I do not know if this is going to break other things on your system.