How to embed a KB in a site on another domain

How to embed a KB in a site on another domain

I want to embed a sub category of my KB ( https://helpdesk.ontwerpfabriek.com) in a second site.
Linking directly to answers using a Lightbox-popup (iframe). The 'X-Frame-Options: SAMEORIGIN' header is preventing this. Is there a way to modify the Content Security Policy Policy header? Or another solution?

ASAP doesn't suffice because it's KB starts with the top most category. And I don't think deep linking to an KB article in ASAP is possible. Or is it?