Hi, I hope you're doing well!
The product pages and documentation for the JN5189/JN5188 were recently published, and can be found starting on this page of our website here.
The JN5189(T)/JN5188(T) User manual can be found here.
As for the SDK, it is still currently rolling out, and it will be available for download from the MCUXpresso SDK builder in the coming days.
Please let me know if you need any more information.
Best regards,
Sebastian