Pramaoy to Phnum samkos wildlife sanctuary

Hello, we arrived in Phumi Pramaoy today because we would like to visit the Phnum samkos wildlife sanctuary tomorrow. Unfortunately, none of the locals we have asked so far know anything about it. We also can't find a tour that we could book. We would like to hike and see wildlife. Does anyone have any experience or can help us?

Another question: we would like to travel on from Pramaoy to Koh Kong on Monday. Is there a public bus? So far we have only been offered taxi rides for 20 dollars per person, which seems expensive as we paid 5 dollars per person for the Pursat to Pramaoy route.

Thanks for your help!