Baine and Talanji are basically saying "this is far enough and we will get mad if she goes any further!" But not to Sylvanas herself? Just to us?
Sylvanas has not agreed to either tone down or told them to shut up - because they have not even brought it up to her yet?
Baine and Talanji are telling us and anyone in earshot that if Sylvanas does anything else, they will bring up the mounting grievances?
Or do they intend to actually do something immediately?
I suppose that will be covered in the telling of the tale. They are waiting a while. Talanji knew about the Forsaken and the Horde's Undead Warchief already. What was she expecting.