There is a solution, but it's a tricky one.
1. The $directory-listing, which get's its ID from the current Post (it's supposed parent) does not return the "To be created" post ID, but the ID of the page/post where you insert the Form.
This is expected, as at this time, no Post ID (no post object) is created at all, hence it can only fall back to the current page/post.
2. Therefore you would need to get the Parent Post ID from the Toolset Forms URL parameter that sets the parent:
parent_{parent-post-type-slug}_id
This could then be called in a ShortCode using the Views "Search Parameter" ShortCode:
[types field="email" id="[wpv-search-term param='parent_{parent-post-type-slug}_id']" output='raw'][/types]
But this will fail because there are more than 2 layers of nested apostrophes, hence you cannot alternate single and double apostrophes anymore and WordPress itself will destroy the ShortCode before it's output.
3. Natively in Toolset Forms, you can display these parent data:
[cred-post-parent get='id']
[cred-post-parent get='title']
[cred-post-parent get='url']
https://toolset.com/documentation/user-guides/cred-forms-for-child-content/#information-about-parent-items
Again you cannot use this, to populate the ID of a Field ShortCode, since it has apostrophes on it's own.
However that I made this work with this code:
[cred_generic_field field='email_here' type='email' class='' urlparam='']
{
"required":0,
"validate_format":0,
"default":"[types field='email' output='raw' id='[wpv-search-term param="parent_toolset-post-type_id"]'][/types]"
}
[/cred_generic_field]
But, remember that the apostrophes are tricky.
