Programatically change to field of an action

I am building an affiliate site wherein a customer of an affiliate can send a form to the affiliate’s email address.

My setup is each affiliate has their own landing page with their pic, bio, and form. Instead of creating a form for each affiliate in their own landing page, I decided to reuse just 1 form with a hidden field with value of {querystring:aff} (see the link of the page I need help with).

The value of the aff in the URL is actually the username of the affiliate (this should not be email address).

I pull the data of the affiliate by using the hidden field’s value upon submission and built-in wordpress function get_user_by();

I used 2 different filters to process the ‘to’:
1. ninja_forms_submit_data to add the value from get_user_by() to the form settings
2. ninja_forms_submission_actions to pull the data from the form settings and change dynamically the action’s to field.

Both filters are in Submission Processing Hooks

Am I changing $action_settings[‘to’] correctly or not? Is it possible to change the to action settings dynamically? If yes, how should I be doing it?

I tested the method I used but it 24H has already passed but I haven’t received the email.

The page I need help with: [log in to see the link]