Alas, if you follow this advice to mitigate this particular risk, you're completely hosed if your cloud account gets taken down or compromised. Which is why the standard advice is to do exactly the opposite and make sure your domains and DNS are separate from your cloud provider.
You can have another cloud platform configured with a duplicate nameserver, then go to your registrar and change the nameserver for your domain.Your replacement nameserver would then control any subdomain provisioning.
I think that would deal with the risk somewhat, though could be missing something.
In risk assessment this risk should be resolved as „avoid“, because loosing DNS will be the secondary concern. Data is even more important. I agree that domains should be registered elsewhere and it’s good idea to have the backup of the zone.