Hi there,
No I would say it’s not possible looking at the Sense schematic. the 1.8v and 2.8v Camera power supplies , those LDO’s can’t be turned off.
It would be possible if you made a board to snap in between the camera and B2B connector on the S3, then use the extra io D11 & 12 perhaps with some FET’s to switch off those or to cut the VSS/VIN to the daughter board all together would be nice. 
But not in the current form.
HTH
GL 
PJ
check out the schematic on the wiki you will see what I mean. 