I realise that the latest version of the Ad hoc database queries report plugin is quite old - I'm using version 3.2 for Moodle 3.0+ (2016080300) - so maybe not being maintained any more. Just want to make sure I'm not missing something.
I have some ad hoc reports which are to be accessed by certain individuals only, these users have been given a role with report/customsql:view set to allow.
In Moodle 3.1.1 (using Essential theme) the report viewer user can access the list of reports in the admin block on the front page, or the dashboard.
However in Moodle 3.3.2, (I've done a clean install today - Moodle3.3.2+ Build: 20170915 - and just added the Ad hoc database queries report plugin and Essential theme), the administration block is only visible for admin users, not the report viewer user. I can add the administration block to the dashboard for the report viewer user but it is empty. This applies to Boost, Clean and Essential themes.
I guess I could put a link to the reports in an html block on the front page, but would have to fiddle around with permissions so only the required users could see it.