they made an artist alley account that auto-posts new user submitted ads. like, OK. In order for this to work you have to know about this specific account and then follow it. The only way you know about this is if you keep up with the cohost corner.
there is a way easier solution here: just use some of the space in the right hand column to actually display the user ad. I understand that is never going to happen because the devs have picked the weirdest ideological hills to die on, but that's the solution. user ads are not going to be impactful if you make users root around for them. you're trying everything but the thing that is going to work.