Updated following pokemon when fainting due to poison.

src/field_poison.c

@@ -3,6 +3,7 @@
 #include "battle_pike.h"
 #include "battle_pyramid.h"
 #include "event_data.h"
+#include "event_object_movement.h"
 #include "field_message_box.h"
 #include "field_poison.h"
 #include "fldeff_misc.h"
@@ -102,6 +103,7 @@ static void Task_TryFieldPoisonWhiteOut(u8 taskId)
             else
             {
                 gSpecialVar_Result = FLDPSN_NO_WHITEOUT;
+                UpdateFollowingPokemon();
             }
             EnableBothScriptContexts();
             DestroyTask(taskId);