Hello Bhavik,
You could change the HANA WD settings as well.
Instead of using the hostname to identify the correct HANA container, the HANA WD could be configured to open multiple ports (one port for each HANA container, instead of one hostname to each HANA container).
Then, SiteMinder would have to be adjusted as well.
But instead of setting the HTTP header HOST, it would have to send the connection to the correct port.
Regards,
Isaías