Decommissioning Old Domain

Hi All,

I have an old domain left over from a migration done some time ago. I want to clean it all up. So far I have removed all the objects underneath it including the old PO. When connected to the "old" domain it sees our new one as an external domain.

I have removed the link between them whilst connected to the "old" one.

Is it safe to delete the "new" one when connected to the "old" one so that it no longer sees it? I can't remember whether that affects the new domain at all.