The new option is there and checked, but the problem is still not solved. Druid will still dismount.
The pictures show a new setting of 3 max mobs near, but this should not matter. It should not dismount.
It also shows a druid fight class loaded, but I also tried with no fight class.
[Normal] 05:33 - Farm Silkweed > 287.2188 ; 445.0938 ; 146.2842 ; None
[Normal] 05:34 - Farm successful
[Normal] 05:34 - Player Attacked by Glade Hunter (lvl 86)
[Normal] 05:34 - Dismount
[Fight] 05:34 - Cast Cat Form (Cat Form)
[Fight] 05:34 - Cast Mangle (Mangle)
[Fight] 05:34 - Cast Mangle (Mangle)
[Fight] 05:34 - Cast Mangle (Mangle)