Ah good to hear. That clears a lot of misunderstanding.
Ignoring the Boot Repair error re Locked-NVram, does everything else work as expected when you boot Pro from your internal drive?
If true, and that Boot Repair error does not impact your use of ZorinOS, then it maybe is not so important.
EDIT: @Julie before you first went and installed ZorinOS on this laptop, did it have Windows on it? I am wondering if Windows was wiped before first disabling "fast-startup" in Windows Power Options. Ref: Before you install