Use Shopify Collection Metafields as page title tag for international seo

Question

I've been working on this for a while and havent been able to come up with a solution. We have a shopify store with various markets (each under their own tdl). For SEO, we want the ability to have a country specific page title tag for each collection. I've created metafields for the collections, and populated with a page title we want to include.

collection.metafields.pgtitle.aus
collection.metafields.pgtitle.usa
collection.metafields.pgtitle.nzl
collection.metafields.pgtitle.global

I've created a snippet to include when page type = collection:

{% if localization.country.iso_code == 'AU' and collection.metafields.pgtitle.aus != "" %}
<title>{{ collection.metafields.pgtitle.aus }}</title>

{% elsif localization.country.iso_code == 'NZ' and collection.metafields.pgtitle.nzl != "" %}
<title>{{ collection.metafields.pgtitle.nzl | metafield_text }}</title>

{% elsif localization.country.iso_code == 'US' and collection.metafields.pgtitle.usa != "" %}
<title>{{ collection.metafields.pgtitle.usa }}</title>

{% elsif collection.metafields.pgtitle.global != "" %}
<title>{{ collection.metafields.pgtitle.global }}</title>

{% else %}
  {%- capture seo_title -%}
    {%- if request.page_type == 'search' and search.performed == true -%}
      {{ 'general.search.heading' | t: count: search.results_count }}: {{ 'general.search.results_with_count' | t: terms: search.terms, count: search.results_count }}
    {%- else -%}
      {{ page_title }}
    {%- endif -%}
    {%- if current_tags -%}
      {%- assign meta_tags = current_tags | join: ', ' -%} &ndash; {{ 'general.meta.tags' | t: tags: meta_tags -}}
    {%- endif -%}
    {%- if current_page != 1 -%}
      &ndash; {{ 'general.meta.page' | t: page: current_page }}
    {%- endif -%}
    {%- assign escaped_page_title = page_title | escape -%}
    {%- unless escaped_page_title contains shop.name -%}
      &ndash; {{ shop.name }}
    {%- endunless -%}
  {%- endcapture -%}
  <title>{{ seo_title }}</title>

{% endif %}

The logic sees to work well, I can see the tags showing where expected, issue is the metafield is not showing, so the result when the condition is met is:

<title></title>

I'm placing this in the theme.liquid file.

How can I get these metafields to show?

Thanks in advance!