if there are multiple pictures, i'd go to the character's profile, then click manage images. from there click manage images (it has a little icon next to it), and then highlight all of the hidden images, look to the right where it says 'visibility' and choose your desired viewer visibility (you can see where it says 'public viewers see...').
this method works best on desktop, not mobile, btw!
I recently got a new guy and noticed that for the public all but one photo is hidden! How do i unhide them??