Does this mean: - a trooper drops the supply box when it enters a marker state, or - a trooper can not enter a marker state while carrying a box? As far as I have seen there is no other way for a trooper to willingly drop a Supply Box (Say in the safe area in Provisions ITS17). So if it is the latter, it seems to give troopers that can go into marker state an unintended advantage to be able to drop their box in the Safe Area. Since even unattended they are considered to be controlled by that player there.
I think you're correct: there's nothing to stop you from re-entering camo. Neither the camo rules nor the rules for supply boxes explicitly state that you can't enter a marker state while carrying the box. Once you enter a marker state, you trigger bullet point #2 for the Common Rules of Supply Boxes, which is what you've posted. Since you cannot carry the box, your trooper must drop the box. In the end, you're spending the same amount of orders to drop the box in a Safe Area by entering camo than if you did it the normal way, so there isn't really much of an unintended advantage. It's arguably an advantage if you wanted to drop the box in any other location for whatever reason.
“If a Trooper is carrying a scenario element such as a Supply Box, what happens if the Trooper enters a Marker State?" A Trooper carrying a scenario element cannot enter Marker State. [Infinity FAQ N5 v5.0.0], p. 2
