Hi, @schalkneethling, and welcome to the Netlify community site. 
The provisioning of the SSL certificate is dependent on the DNS configuration for the domain. The most common cause of these types of issues, delays in changes to DNS records:
It is possible that deleting the DigitalOcean droplet affected the DNS records but I’m not aware of how this would have happened. It is possible that this was the change that was required.
Does DigitalOcean also control the DNS for this domain? If so, that might explain why deleting the droplet affected the DNS.
If not though, I strongly suspect that deleting the droplet was a coincidence and that TTL values and DNS caching were the real root cause.
If there are other questions about this, please let us know.