Hi there!
Apologies for the confusion. Since the mini-cart is displaying correctly for both desktop and mobile headers for free versiobn of Kadence theme but is not working when using the Advanced Header with Kadence Pro, I recommend reaching out to the Kadence Pro support team. They should be able to help you configure the mini-cart for both mobile and desktop headers. There should be a setting within the theme that allows you to add the mini-cart block for both.
Regarding the grayed-out issue: Since you’ve already placed the block in the header, WordPress automatically grays it out to indicate it’s in use. This isn’t related to a WooCommerce issue.
Also, the ticket link you shared refers to the same header template for both mobile and desktop, which is why it couldn’t add the header. My colleague has already provided a solution in that ticket to add the mini-cart for the mobile header. I suggest reviewing the response from Shameem in that ticket for further details.
Thank you!