Stick to the main path with stealth

The path is long, and you take your time to prepare an invisibility spell. Natural barriers block your pass; the only way to continue is through the goblin village.

You arrive at the goblin village; you spy between the dense vegetation, far away from the palisade. You notice a chaotic jumble of huts, caves, and wooden fences. At its center is the chieftain’s dwelling, a grotesque structure of scavenged wood and bones with a red banner flapping in the wind. But another building catches your attention too, a windowless fortress of blackened woods; its walls are reinforced with jagged spikes, and goblin sentries patrol around it, scanning for threats.
Whatever’s inside, they’re terrified of losing it.

• You can check the chieftain's dwelling for any valuable goods.
• You can check the mysterious structure for more hints
• You can take a detour through the wild woods and forget about this nightmarish village

What do you do?