^^
The last 2 years before Carine's departure marked the rise of Social Media and streetstyle and somehow, Carine became a little celebrity and she enjoyed it (it's her right and her great style was enough for it to happen). Even if she was very influencial already, fame gave her new opportunities.
Since her beginnings as the EIC of VP, she has always done side projects (she styled the Gucci and YSL campaigns under TF at the time), but around 2009, she wasn't even hiding it. She wanted all .
The Tom Ford issue was the ice on the cake because 2010 was a very controversial year for VP. They were banned from Balenciaga earlier in that year, that caused speculations and raised a few eyebrows. And the brand pulled it ads from the magazine.
The Tom Ford issue was really A Tom Ford issue. Even if Tom Ford is an "annonceur" and has the Estee Lauder brand behind, he is not the biggest advertiser compared to LVMH or Kering. Even when his clothes weren't used, his vision was very overwhelming and let's not forget that Tom didn't left Kering on good terms and did everything possible for Bernard Arnault to not buy Gucci. With those backstories and then the controversial issue, it was like the perfect goodbye and i'm sure she already knew by the time that her time was up at VP.
I don't know about MAS.
At the time i heard she left. I think the firing part might be a rumor...