Yes, it is 2.4-D damage. Can see exactly the path it took and where it came from. We think the neighbors burned some empty jugs that had 2.4-DB. The fumes from that is what we think got the cotton. 

Could be we're way off.

Could be they cleaned their boom out right there and it drifted across. 

 Neighbors water filling station with still full 2.4-DB jugs sitting there.

View from the the damage spot to the neighbors water tank etc. 

Last year we had damage in the same spot from the same guy. It was from them spraying peanuts then as our neighbor to the east had damage too from the same guy. 

Looking across the rows. 

One of cotton's biggest enemy's is 2.4-D. You can drive across the turn row with an open jug and the cotton will die from it.