asa can be ezvpn client
and on the router the server side of the vpn
u need to add RRI
reverse route injuction on the dynamic-map
One key component of routing in a VPN deployment is Reverse Route Injection (RRI). RRI places dynamic entries for remote networks or VPN clients in the routing table of a VPN gateway. These routes are useful to the device on which they are installed, as well as to other devices in the network because routes installed by RRI can be redistributed through a routing protocol such as EIGRP or OSPF
in this case when the ezvpn client connect its route will be added to the server vpn
good luck
please, if helpful rate