It seems the new area is more of a tiny chamber than a passage. On the stone floor lie the skeletal remains of at least two large-ish creatures, covered with the dust of countless years. ((Knowledge: Dungeoneering to ID the remains.))
The wall has been carved into an ornate design (reminiscent of the runic language everywhere else, but without meaning), which incorporates several hooks. Hanging on one of the hooks is a dust-covered forest-green cloak of excellent make, with gold embroidery around the edges.