Rene is correct. Just because the neighbor statement is used with an IGP does not modify it’s TTL. Whether RIP or EIGRP are sending their hellos/updates via multicast or unicast, the TTL is 2 in both cases. For OSPF, PIM, and LDP, it’s always 1.
If you used the neighbor statement with OSPF, the TTL remains 1. So, simply by modifying the behavior of the IGP does not modify the packet’s TTL.
The reason behind this is to still maintain neighborships across NBMA networks, including DMVPN, for distance vector routing protocols WITHOUT having to disable split horizon at the hub.
Another fun trivia fact: TTL=2 is the reason why RIP and EIGRP packets will hit under “control-plane host” and TTL=1 explains why OSPF, PIM, and LDP will hit under “control-plane cef-exception”. So beware of your protocols in use when configuring CPPr.