Hello Mohammad,
It 'can' relate to the main issue depending on how your cluster is set for communication.
You need to go into CLI > Clusterconfig > Communication
Confirm the IP and ports used for communication between devices.
Run a telnet from both devices to one another on the right IPs and right interface to be used on port 22
Timeout means your ESA's are unable to communicate with eachother via the means setup on the cluster communication, normally a network error
As for your adding of IP into the RELAYLIST; this depends.
Is the LB acting as transparent (IE: it just transfers the connection with original source IP) or is it taking over the source IP before connecting to ESA.
Perhaps it would be good to add the IP of the HT servers instead (in the event your LB is transparent) and it should correct the nature.
As for the routing table and gateway.
If your current default gateway set (CLI > setgateway) is not reachable by data2. then you need to add an extra routing table for the data2 to use for a default gateway else it will not be able to reach out.
Regards,
Matthew