Yes, you are absolutely correct, to forward your noble and forthright suggestion.
To be honest, as it is now a bit over six years ago, and I am not absolutely sure as to exactly what I did with those few remains of this drone, nor do I have any idea what happened to the battery, or the propellers and any other bits and pieces, which were not found at the site. The drone 'remains' were neither found nor left where they were imaged.
My "left at location, as a warning to others..." was intended as a 'poetic' ending to the saga, not an actual sequence of events. The potential for someone injuring themselves on those corroded remain in a public place was all too evident to this electrical engineer.
We all can contribute more to assist our environment, and am delighted that you took the time to write.