RTP Dialogue pop up campaign for anonymous visitors

Hello community!  You have been very helpful to me lately.

I get that RTP is best used for delivering custom experiences for known individuals, but what if I want to display a dialogue popup box experience for anonymous visitors?

Here is what i'm trying to do:  we have various web campaigns tied to segments for known individuals. In addition, we want to have a separate dialogue pop up for everyone else (anonymous, unknown individuals - someone who hasn't clicked in a marketo email or filled out a form).

To do this, do I simply create a segment that is: Known Profile --> Status --> Anonymous?  With the other campaigns running, I would prioritize this lower.

Am I thinking about this right?  Any ideas, examples, or advice on how to deliver RTP dialogue campaigns to the anonymous visitor would be appreciated!