Custom content several pages and regions loop

Using Blocks and perch:template. So Product Groups and Products are sharing the same code and id's. Reusing the same templates for all the data just products have more detail added obviously. I only need to grab minimal data as above, so what I need is common on both Groups and Products.

<!--* Main heading and introduction and graphic *--> <perch:before> <perch:template path="content/blocks/introduction_block.html" /> </perch:before>

<perch:blocks divider-before="Choose content block to suit you're content as many or little as you want, you can even reorder them.">

<!--* Key Features *-->
<perch:block type="key-feature" label="Key Features">
    <perch:template path="content/blocks/key_features_block.html" />
</perch:block>

<!--* Heading & Text - Option to select h2,3,4,5,6 etc via dropdown *-->
<perch:block type="title-text" label="Heading and Text">
    <perch:template path="content/blocks/text_block.html" />
</perch:block>

<!--* Lists used for things like Features or Benefits *-->
<perch:block type="text" label="Information List">
    <perch:template path="content/blocks/list_block.html" />
</perch:block>

</perch:blocks>

ps. this page won't load for me: https://support.grabaperch.com/formatting

All data is added per page and region, NOT list and detail.

Custom content to load and list groups and products on: /products/index.php

Product Groups: /products/group-name/index.php template = Group_detail.html

Products (multiple): /products/group-name/product-name.php template = product_detail.html

Both above share Blocks with some extra for Products, but I don't need to grab any of the extra data.

So on a certain Group page I'm also listing products within that group page like so:

// Get URL segment 1
$segments = explode('/', PerchSystem::get_page());
$group = PerchUtil::html($segments[2]);

    perch_content_custom('Product detail', array(
        'page'=>"/products/$group/*",
        'template'=>'_group_product_listing.html',
    )); 

Does that make sense?

yes that's correct, so listed on the page it would have X Product Group and associated Products, then the next X Product Group with it's associated products and so on until they are all listed.

I can get both sets of data e.g. Group & Products but not combine them. As the group and product data is from different regions I don't understand how to load the group from one region and page and then process products in that group data before moving onto the next group. I can only get the data to load separately not combined.