How to set up a non-authoritative name server with Microsoft DNS Server

The delegation seems to be in place and your nameservers appear to be responding.

However, your nameservers would appear to deny the existance of any NS records for the zone, something which is definitely not a good thing. (Whether or not it fully explains the problem is unclear to me as the problem description itself is somewhat vague.)

I would suggest dig +trace +all commissionconverter.com NS to see more or less the steps that a resolver server would go through to look up a name (start querying for the specified name at the root, follow delegations, repeating that process until done).

As you can see the result of the very last query, the one directed to oen of your servers, the server does not respond with the expected NS records.

It's possible that there are further problems to be found in your case but this at least covers some of the fundamentals and points out one problem.

Many registries use the Extensible Provisioning Protocol (EPP) to facilitate their registrar interactions.
It's worth noting that this is a whole separate protocol from DNS itself, specifically dealing with name registration and provisioning. It only indirectly populates the relevant zone in DNS.

Unless you are either a registry or a registrar it really doesn't matter much what sort of protocols / APIs these parties use but if you do want to read up on it, here are some of the relevant specs for EPP:

• Extensible Provisioning Protocol (EPP)
• Extensible Provisioning Protocol (EPP) Domain Name Mapping
• Extensible Provisioning Protocol (EPP) Host Mapping
• Extensible Provisioning Protocol (EPP) Contact Mapping
• Extensible Provisioning Protocol (EPP) Transport over TCP
• Domain Name System (DNS) Security Extensions Mapping for the Extensible Provisioning Protocol (EPP)

As more of a sidenote, the root servers deal with the root zone (aka `.`), a TLD zone is not the same as the "root". If you register for instance `example.com` through your registrar nothing changes in the root zone, your delegation is only entered into the `com` zone.