Thanks, we found that this is also working to noindex the vendor pages. What code did you use to stop writing the query into the title tag? I tried this but it ends up breaking the title tags on each page and only prints the url of the page.
{%- if request.path == ‘/collections/vendors’ and collection.all_products_count == 0 -%}
No Results Found {%- else -%} {{ seo_title | strip }} {%- endif -%}