Knowing older, mellow dogs, I bet you'll find that Hopi will sniff then ignore your baby. Once Hopi is bored and goes off to sleep, or whatever, Maddie will become braver and start checking out her environment and even seeking out Hopi. All they need is time.
Don't leave them unsupervised until you know that they are okay together, though
Before long I bet Maddie will be excited when she knows she's going to visit her good buddy.
