How to display Joomla User Custom Fields in Gridbox Account / File Management View?

Dear Gridbox Support Team,

I am using Gridbox 2.x and the Account (Customer Account) module for my website's "File Management" area. I need to display a specific Joomla User Custom Field (Name: notion-url) directly within the User Account frontend view so that logged-in users can see a personalized link (e.g., a Notion project board) assigned to them by the administrator.

The Issue:
I have tried using a standard Joomla System Plugin to inject JavaScript into the ba-item-customer-account container. However, because the Account module renders dynamically via ba-account.js, my injected content does not appear consistently or is overwritten by the Gridbox rendering engine.

My Questions:

Is there a built-in way to map/display Joomla User Custom Fields within the Gridbox Account module?

If not, what is the recommended JavaScript event or PHP override I should use to ensure my custom content remains visible after the Gridbox Account module finishes loading?

Can I use the "System Pages" editor to add a dynamic field that pulls data from the logged-in user's custom fields?

I have already verified that the field name is notion-url and that data exists for the user. Any guidance on how to properly hook into the Gridbox Account view would be greatly appreciated.