When you've reached the keyhole tree, solve the following clue:

50 / 10 = __ x 2 = ??

Then play the audio:

6.1 KumarEnchanted Treasure Trail
00:00 / 00:32

Show the image:

Artwork by Dapinder Chahal

Can you see Kumar's face yourself?

Directions:

Keyhole Tree to Barnes Stn.png