Problem extending object classes in AD LDS

Hi

I'm trying to add the Organization classSchema as an objectClass to the top level domainDNS classSchema(which is dc=domain,dc=local.) in an AD LDS instance. 
Default objectClass on top level domainDNS are domain, domainDNS and top. I want to add organization.

On the Organization classSchema, possSuperiors is set to domainDNS, also tried domain and container.

Getting the following error: 
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ADSIEdit
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Operation failed. Error code: 0x20b4
The specified class is not a subclass.

000020B4: UpdErr: DSID-030F1563, problem 6002 (OBJ_CLASS_VIOLATION), data 0

Tips appreciated.