That’s for the ACME server, i.e. when Caddy acts as the ACME issuer for self-managed certs. That does not apply to public issuers like Let’s Encrypt and ZeroSSL.
If issuance works, renewals will work. There’s no reason to try to force renewals. It’s the exact same process, except for a minor change in the data sent to the issuer in the API calls.