I am not sure. But the first VPN (AdGuard) in your screenshot establishes a local VPN on your iPhone. If you now set up the "normal" VPN with IPsec, it will get in each other's way.
Maybe there is someone more competent here who can give you an educated answer.
True. Not a very lively forum.
The first thing I would do is update both AdGuard and Monterey. There are new versions of both.
The second thing I would do is delete everything under Safari Einstellungen-Datenschutz-Websitedaten verwalten.
Which macOS?
Which AdGuard version? (I suspect AdGuard for Safari).
I also added the exception and have the same problems as you. You have to turn off AdGuard completely for the page to show. Under Safari it is only displayed shot up. Under the Brave browser correctly.
In AdGuard for Mac you...
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