WordPress plugin - Hard Rejected with no explanation

Hello everybody, we are a development team and we created a WordPress plugin that adds an advanced search interface inside the wordpress admin: at the top of any post type list (either standard or custom) you can open a search box to easily find posts by title, content, date, author, status, etc. You can also specify complex search queries (date intervals, logic conditions between fields, etc.)
We already published it to the official wordpress.org plugin repository (Advanced Post Search) and we already got some positive feedbacks from users.

We also developed a PRO version, that enables the posts search by custom fields (created using Advanced Custom Fields plugin), so you can configure the plugin to filter posts by any of the custom fields you have created (custom text fields, checkboxes, drop-down menus, images, relation between posts, and so on).

We sent the plugin PRO version to Envato Review Team, but they hard rejected it without giving us any explanation.

How can we sell our plugin on Envato platform?

It is very hard to understand the reason why they rejected if they don’t tell us: the plugin is actually working, the interface looks nice (and uses standard wordpress UI elements) and the search functionality is really useful when you have to manage a lot of records inside your wordpress database. We think our plugin is more useful than (or at least as useful as) many other plugins on Envato Market.

Could you give us some feedbacks? Thank you!

PS: we are developing others features, such as front-end public search (with auto-generated forms), WooCommerce support, and so on, but it’s sad working on it without knowing if we can actually sell it on this popular market.