[denphi]

getToolExportAccess() creates $export_access as a bare stdClass, then every denial branch writes to $export_access->error->message. Under PHP 8 assigning a property on null is an Error, so each of the five refusals -- unknown location, E1 nation, US-only, D1 licence and Purdue-only -- killed the request instead of returning the denial.

It only ever bit users who were refused, which is why the tool pages looked healthy for everyone else.

Initialise ->error the same way the sibling getToolAccess() already does. The sole caller reads only ->valid, so nothing else changes.

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