When Ad Inserter detects that the settings page was not loaded properly it shows a warning message (Page Blocked):
https://adinserter.pro/documentation#troubleshooting
Ad Inserter does not and can not detect if anything on the frontend (what is visible to the visitor) is blocked. In fact, there are only the ad codes you configure and wrapping divs.
Wrapping divs use class name that can be changed so Ad Inserter as plugin can be made undetectable.
https://adinserter.pro/documentation#plugin-settings
But there is no universal way to detect if anything is blocked. Usually, each ad code uses some javascript code which ad blockers block, so you can write custom code to see if the script was loaded/blocked or not.
If the ad is blocked in the browser then it is blocked – not loaded. You can only try to detect if it was loaded but each ad would need a custom code.