One of my shared, multiple item regions is not appearing in search results

Hi, I have a multiple item region which won't ever appear in search results, it's also a shared region.

I have the option to include in search results checked in the region options. This is happening on both the dev and staging server. I can't for the life of me figure out what could be causing this issues.

Diagnostic report included below:

Perch: 3.0.10, PHP: 7.1.4, MySQL: mysqlnd 5.0.12-dev - 20150407 - $Id: b396954eeb2d1d9ed7902b8bae237b287f21ad9e $, with PDO
Server OS: Darwin, fpm-fcgi
Installed apps: content (3.0.10), assets (3.0.10), categories (3.0.10), perch_blog (5.6.1)
App runtimes: <?php $apps_list = [ 'perch_blog', ];
PERCH_LOGINPATH: /perch
PERCH_PATH: /Users/Andrew/Code/llwperch/perch
PERCH_CORE: /Users/Andrew/Code/llwperch/perch/core
PERCH_RESFILEPATH: /Users/Andrew/Code/llwperch/perch/resources
Image manipulation: GD
PHP limits: Max upload 128M, Max POST 128M, Memory: 128M, Total max file upload: 128M
F1: 3b606135b33e6a102526838f4152a807
Resource folder writeable: Yes
HTTP_HOST: llwperch.dev
DOCUMENT_ROOT: /Users/Andrew/Code/llwperch
REQUEST_URI: /perch/core/settings/diagnostics/
SCRIPT_NAME: /perch/core/settings/diagnostics/index.php

It seems as though search for all other regions is working as expected.

Any suggestions on what might be causing this and how I could resolve it are greatly appreciated ;)

Cheers, Andrew