Hello @d0153, I did submit a support ticket without having the issue be resolved unfortunately.
Which is why I am reaching out to the public and hopefully find someone who has had success in implementing custom filtering to the filter bar on the new 6.x version of the plugin.
The 5.x version I have had success numerous times but unfortunately ability of creating custom filters on the filter bar is no longer possible based on what I can find and what I was told via the support ticket.