iFrame on different domain

Right. This exactly what is written in the quick start guide.
No one can do this without access.

You can use the hide elements features that works also on remote domains. See https://www.tinywebgallery.com/blog/advanced-iframe/advanced-iframe-pro-demo/hide-a-part-of-the-iframe

With access you can hide stuff with really removing if from the site. Without like in the demo above you place divs with a specific color over the iframe so that the content below is not visible anymore.

Please use https://www.tinywebgallery.com/forum/ for support of the pro version.

Best, Michael

Super, very helpful! Thanks a lot
Best
Edyta