Managing a subdomain

We have an issue where we need to control which server DNS points to for our subdomain. i.e sub.somedomainz.com -> we do not control the primary DNS server for somedomainz.com, but the people in charge of that would be willing to point to our DNS for the sub domain.
Am I just completely crazy is something like this possible.

THe reason is we are doing geographically dispersed clustering, and our clusters, need to be able to update DNS . We cannot just get our own domain it must be a sub of the main domain. The people who manage this domain will not let us update the DNS via scripts, so we need that sub domain managed on dns servers that will allow us to script updates, when one server fails so traffic is sent to the correct servers.

Hopefully this makes some sense?

Any suggestions!