Unchartered Island — Blaze Eastwood

A soldier gets caught off from his platoon in the middle of a foreboding jungle. Before long, he encounters a dinosaur after venturing into a canyon. He is never seen alive again.
Forty-five years later, Brendan and Ashley become familiar with the stories about the unchartered island. They go cruising on a boat, and decide to venture through the island, convincing themselves that as long as they don't go too deep into the jungle, they'll be okay. But after encountering and nearly being killed by a dinosaur, they end up losing their path that leads back to the shoreline.
Now they must wander through the depths of the jungle, not knowing what lurks behind the rustling foliage or the mossy swamps that envelop them.