Hello Kaza
Note that the configuration in this lesson is using DMVPN Phase 2. This means that the routing information found in each spoke contains the IP address of the spoke as the next-hop IP. This is because Phase 2 allows for spoke-to-spoke GRE tunnels.
The hub will never change its next hop to an IP that is “behind” the hub, but it will inform the spokes of the topology of the IP addresses of the other spokes, using NHRP. You can find out more about this in the following lessons:
As for the add path support feature, the only thing the hub will do is to ensure that multiple spoke IP addresses appear as the next hop for particular destinations behind specific spokes. Remember once again, that we have direct spoke to spoke communication, so there is no scenario where traffic will go “behind” the hub router only to be routed back into the DMVPN infrastructure.
I hope this has been helpful!
Laz