If you have stateful services configured the traffic flow between VMs would be:
VM1 > T1DR > T1SR > T0DR > T1 #2SR > T1 #2 DR > VM2.
This is assuming that every flow from VM1 must hit the stateful service on the way out and must also traverse the stateful service on the second Tier-1 gateway. Remove the SR's where not required.
On the way out
VM1 > T1DR > T1SR > T0DR > T0SR > out
FYI, a stateful service is LB, NAT etc, just attaching an Edge cluster to a T1 is not exactly a stateful service, even though it makes the gateway active-standby. It's best to not attach the edge cluster to a T1 when there are no services being configured.
Also the packet does not hit the same gateway twice within the one flow (like you have depicted in your first post).
Hope this helps.