Are you creating the datacenter and DVS info before or after you import the key to vCenter?
Just to be sure the correct order of steps should be
1. export extension
2. import extension in vCenter
3. Create Folder/Datacenter/DVS info
4. Create port-profile
5. create port-profile client
6. Add esx host to UCS DVS in vCenter
7. Add VM to the port-profile
Also make sure you have a vCenter Enterprise Plus license. Because a DVS is created you must have the Enterprise Plus license. Also we expect communication between vCenter and UCSM to happen on port 80. Sometimes folks change the default port from 80 to something else. Last make sure the Datacenter and folder names that you setup in UCSM match exactly what is in vCenter. That means any spaces or capitalization need to be the same in the UCSM config.
louis