I had same issue on live server few days ago, at first all camps were invisible. But camps started to appear on map when I was getting close to them. But other camps (which I was never been close in that session) were invisible on minimap.
I and other people had same bug in live servers long time ago, maybe even before ptr. For me gates were disappearing and sometimes it was enough to reopen map, but sometimes I had to relog. It happens rarely and randomly so I didn't bother reporting.