Dynamic content for third party (website) mautic 3.3

Your software
My Mautic version is: 3.3.3
My PHP version is: 7.4
My Database type and version is: not sure

Your problem
My problem is: Get dynamic content to work

These errors are showing in the log:

Steps I have tried to fix the problem:

I dont know maybe is time for a docu update? Documentation for this is and other issues on mautic.org is so outdated, at least 6 years old.

Anyway couldn’t find anything on third-party dynamic content besides one line of code.

<div data-slot="dwc" data-param-slot-name="??????????">
  <h1>Dynamic web content for myslot</h1>

The main issue is there is no slot name available on mautic 3.3.3 which is the version I’m at.
Secondly, I need to serve images according to locations.
So in the first slot I’ve one image and the second another one.
Ive created a campaign with a location segment, so according to user location they should see
the different images, I still need to test this though.
Is this the correct way to set this up?
Can someone advise on this?