You can’t hook an Element into your existing content between blocks, unfortunately. Hooks only work where the code for the hooks exist, and that code can’t exist inside the content you build.
Maybe there is an opportunity to include in the new version of gp-premium some code that I can add myself to an arbitrary place, the body of the WordPress page (by the Gutenberg block) (by the editor of the page, post, product)? And this code will output a hook?