Has anyone found a geo-cache at the Rothbury Riots memorial?

Hello
We're new to this site (& to geo-caching) but as we were walking a bit of the Great North Walk last weekend -- we also tried (for my son) to find the geo-cache at the Rothbury Riots memorial. Your book's description is good -- we found the memorial OK but no cache. Has anyone seen it?
Cheers
Lara et al