The use case is as follows: I registered the domain schockauth.org on namecheap and delegated the DNS to the digitalocean DNS system. Unfortunately I did not registered the domain in digitalocean management system. Another digitalocean user did register my domain and by having the DNS authority was able to create a certificate with LetsEncrypt.
I noticed the problem when trying to register the domain with the digitalocean management system and it was refused as already being in use. This later problem was easily resolved as I can prove that I own the domain, but the existing letsencrypt certificate is still around.
I would like to trigger a revocation process for this certificate and would need some guidance on how the process would look like. I guess a simple certbot revoke will not do the job, since certbot does not know the certificate to start with.
If you currently have controle over the hostname, you could use the steps under the paragraph "Using a different authorized account". It explains all the steps.
You might also be able to use this Let's Debug tool. I have never used it personally but it describes your situation exactly. https://tools.letsdebug.net/cert-revoke