Thanks for your response!
Here I created a domain "pono.local" using a DNS server, and the full name of "Tommy" was "pono\Tommy". I'd made "pono\Tommy" the organization manager of "Company_Org_vdc" in vCloud and a member of provision group "Pono_Company" in vCAC before I performed the requesting machine operation. I also tested the user "pono\Tommy" in vCloud Director and it worked well.