The way I see it, Objection 1 may not be valid because this is clearly anticipation : we don't know yet if nobody would feel responsible for it anymore (and even if it is so, maybe it's OK for roles in that circle to not care about it, as long as it is taken care of elsewhere). I'd go through the process "do you know for sure it'll happen based on data, or are you anticipating, and if so, would it be too late to course correct it later or is it safe enough to try?".
Objection 2 would challenge the need you had for creating that new circle (capacity building) in the first place. But since it's been created, I don't see why it'd be any less real than any other circle. Go through the 4 questions of the process and I'm pretty sure this one won't cut it (I'd say the objector doesn't act from its roles but is rather trying to help out everyone).
My 2 cents.