I think we shouldn't reject any anti-war initiative no matter which side it comes from. Ultimately anything that weakens and discredits the imperialist war machine is beneficial to the revolutionary cause. This doesn't mean we join forces with reactionaries, but that we don't actively fight against any initiative that for whatever reason advocates against NATO and its global warmongering, even when some very shitty people are involved who have a much different agenda than ours. Let them do their thing while we focus on our task which is to build our own principled working class anti-war, anti-imperialist movement. Wasting our energies denouncing reactionaries who are cynically trying to co-opt popular anti-war sentiments not only weakens the anti-war cause, it also discredits us in the eyes of the masses and is a boon to the reactionaries. If we think we can do better than them and build a more effective anti-war front (and i think we absolutely can because we are coming at this from a principled perspective and not from political opportunism) then we should just do it and not knock other anti-war voices down.
This might be an unpopular opinion but i say it because i really think we have to learn to think and act more strategically and resist the liberal impulses we may have for virtue signaling and purity tests. It is to the benefit of the class enemy that we waste our time constantly criticizing but never actually doing.