First I would like to thank the developer for releasing this plugin for free. 

Problem: a hidden stash can be uncovered by placing a twig foundation over it. The plugin doesn't detect this and won't notify the admins. 

Solution: when the state of the stash changes, find the nearest player and report. Or check the entityowner of the twig foundation that killed the stash.

This specific scenario has been addressed in the most recent release.