ssh_dispatch_run_fatal / DH GEX group out of range

I'm running Ubuntu 20.04 / OpenSSH_8.2p1 and have a client trying to connect but it's failing with error in auth.log like:

Nov 25 02:13:20 sshd[517621]: ssh_dispatch_run_fatal: Connection from 192.0.2.1 port 50127: DH GEX group out of range [preauth]

I did see a few other questions asking about this error:

https://serverfault.com/questions/786587/dh-gex-group-out-of-range/809082
https://serverfault.com/questions/729033/ssh-dh-gex-group-out-of-range
https://serverfault.com/questions/852666/sftp-connection-fails-with-dh-gex-group-out-of-range
https://serverfault.com/questions/920839/ssh-error-ssh-dispatch-run-fatal-connection-to-192-168-x-x-port-22-dh-gex-gro

But all of those questions relate to someone with a newer client trying to connect to an older server and receiving the error on the client end. The best solution in this case is probably to upgrade the client. In my case however, I have no control over the client and since I'm running a very new version, my assumption is that this has to do with the server version being newer than the client.

I'd like our server to accept their connections. Is there a directive I can adjust in /etc/ssh/sshd_config to allow older clients to connect? Or any other solution that doesn't involve asking the client to upgrade their version?