Hmm.
I wonder if there's some special way of finding that out - not really sure. You -could- try
animationPhase? But I'm not sure if that's the way it works, really, although it does look like an animation when the mine goes for "placed" to "disarmed". Besides, you might have to go into the config to find out the names of the animation phases in that case. Alternatively, you could try
vectorUp since the mine is sort of tilted to the side when disarmed - maybe it'll change, with any luck?
Otherwise, since it's the player doing in the clearing, just give the player an action or a radio command that tells the convoy to get moving once he's confident most or all of the mines have been cleared - if he screws up, it's on his conscience.
Good luck!
Wolfrug out.