If his browser doesn't support any of the ciphers you have enabled, that's a problem with his version of Firefox and/or his default TLS library. These ciphers have been around for years and are supported by even some pretty old browsers.
Your TLS config is good for now, unless another padding oracle attack comes along and makes those CBC ciphers weak again, or some other vuln.
(your cert is expiring next month btw, might be a good opportunity to set up LetsEncrypt)