Unable to access tree nodes in the exhibition below belonging to user Cooker.  A similar issue with the same node level happening in Workbench but was resolved.  To see the issue just access the exhibition link.

  http://exhibition.sidora.si.edu/public/PanamaArchaeology 

In WB, the message correlates with the log message:

Notice: Undefined index: xslt in sidora_get_xsl_exhibition_config_for_object() (line 901 of /data/fedora.wb.d7.ocio/htdocs/sites/all/modules/sidora/workbench/includes/xsl_handling.inc).

https://workbench.sidora.si.edu/sidora/open_access/xsl/si%3A2774316