Autoload post

You need to enable remote debugging and post page address:
https://ww.wp.xz.cn/support/topic/ad-inserter-support-before-you-ask-for-help/

It seems that adittional content loaded via Ajax requests is not processed via the_content filter:
https://adinserter.pro/faq/how-ad-inserter-works#infinite-scroll

I would suggest to contact theme authors.

They can contact us, we’ll be happy to add additional support if needed.

No, the only way would be to process post content to insert there.
However, it is standard WP approach to process post content via the_content filter.

Unfortunately no, as the “provider” of the content (template with auto load posts) needs to process the loaded posts via WP filters so the plugins are called and ads can be inserted.

Actually, no “third-party plugin” support is needed. Only following WP guidelines and approaches in order to allow plugins to do their job.