Views is a WordPress plugin that lets you display post relationships.
In our user guides, you can find more information on how to display child posts, related posts, brother pages, fields of parents and fields of grandparents.
When you ask for help or report issues, make sure to tell us the type of the relationship you are trying to build and the structure of your data.
Filter a post view by custom fields of another post type.
Solution:
Relevant Documentation:
It is a limitation of WordPress PHP Class WP_Query: if you are going to filter posts a custom post type by custom fields, those custom fields should be setup in this custom post type, you can not filter the result by custom fields of another post type.