How to get all nodes referencing a particular node?
The Relationships and Aggregation features are fairly limited as they directly work on the database query, so you can only aggregate using very simple functions like COUNT, AVG, MAX etc.

What you are trying to do (load multiple related values for each row, and render them together) can be done with a sub-view, for example with this module: https://www.drupal.org/project/views_field_view

That would allow you to create a separate view ("Nodes referencing a particular node") with a contextual filter, then add this view as a field to the main view. It slightly impacts performance, as each row in the parent view executes a new sub-view, but should be okay with caching.