Agree, Rock throw attacks from Greydwarfs should but turned Off while they are swiming.
It makes no sense that enemies keep to use all their attack options while swiming in water, while the player gets to use only fists.
Not to mention creatures dont use stamina while the player gets drained and debuffed at the same time (being wet) while being near or in water.

Other enemies also still get to use their ranged attacks while in water, not just Greydwarfs.