Failover in the two routers network question

We have 2 CCR1036 routers

First: PPPoE with radius client and bandwidth control.
Second: Routing, NAT and Failover for high priority users.
failover.png
When we used only one router in our network which was a PPPoE server and NAT router in one box, it was simple to allow only high priority users to go through failover link when the main link was down and block failover access for others. However, when we separate a PPPoE server and NAT router, we faced a problem. All dynamic address-list entries that allows failover are on the First router, Second router do not know this address-list and we could only block or allow all to go through failover. Do we need to set address-list on the Second router by script/manually or there’s another way?
Maybe we could mark packets between two routers somehow?