Sorry, I just edited my post for clarification. They are not hiding in BG3, they are infiltrating the circle, trying to take over; this is their main goal. Nature's fury and so on, this is what Faldorn used to be about in BG1 too.
Were they going to go on the offensive once their chips were down and the grove was sealed then? I don't think this is communicated to the player, nor does that sounds anything like Kagha's plan. Maybe the problem is that Olodan gets hardly any lines?