The crucial piece of information in the responses file that needs to be conveyed from the initial cell to additional members of the server group is the private key that the cluster will use to encrypt/decrypt data in both properties files as well as the database. If all members of the server group aren't using the same key, you'll encounter decryption errors.
The most straightforward way to get the additional cells working would be to remove the RPM if it's not already gone and to remove anything under /opt/vmware/vcloud-director/etc to ensure that it doesn't use the old properties files from the bad install. Then re-run the installer and supply the -r option and specify the path to the responses.properties file you've copied over. If the RPM is already installed but you haven't run the configure tool, you can start from that point ($VCLOUD_HOME/bin/configure -r /path/to/responses.properties -- that's all the installer does when it prompts you).
Note that for the permissions on responses.properties; if you've already installed the product the vcloud user and group will already exist (getent /etc/passwd vcloud to check) so the permissions you mentioned should be adequate. If the vcloud user does not (or no longer) exists you'll need to set it to be more permissive -- most likely the read bit will need to be set for other temporarily. i.e. chmod o+r responses.properties before running the installer/configure tool and then remove it when done -- chmod o-r responses.properties.