Getting joined data for widget scope

Dev
4

In using the staff notes plugin for reference, I have tried to make a custom field available to the post-name widget by doing the following:

In plugin.rb:

after_initialize do
  require_dependency 'user'
  whitelist_staff_user_custom_field("myCustomField")
end

In initializer:

import { withPluginApi } from 'discourse/lib/plugin-api';

export default {
  name: "alt-topic-initializer",

  initialize: function(container) {

    withPluginApi('0.2', api => {

      api.decorateWidget('poster-name:after', dec => {
        console.log(dec.attrs.userCustomFields);
      });

    });
 });

The result of my console.log is undefined.

I have tried whitelisting the custom field in Discourse site settings as well.