Hey it worked! The first problem was solved. The devices can now ping each other vice versa whichever is the master switch. Now I know the issue is with the reth and AE interfaces. I have also converted the srx cluster to active/passive.
Only one issue remaining now, there is still downtime when I unplug the member0 switch and connectivity comes back after it has restarted. However, there is no issue with connectivity when I unplug member1 switch. So I was thinking maybe it is still connected with the reth, since reth0 is connected to EX member0 and reth1 is connected to EX member1.
Anyway, there is progress now with our setup. I'll try to troubleshoot further on this downtime. Thank you very much!