I got domain hgpt.xxx (parent domain), and another domain iac.xxx in the same forest of hgpt.xxx. and its was created a trust between these two.. I am very sure there is not existing domain controllers are for this iac.xxx.. when i am try to delete coming up with an error.
When trying in ntsdutil, coming up with an error
"DsRemoveDsDomainW error 0x2015 (The directory service can perform the requested operation only on a leaf object.)
Print screen is attached for your reference.