Permanently Deleted
Working in an org means working with other people even if you don't always see eye to eye
This might not be the first thing you try, but what about asking outright if he wants your position? If he says yes, you have your answer and you can work from there, maybe even indicating that you’d be willing to step aside if he’s willing to be an adult about it and have a conversation about your ongoing participation in the org.
If he says no, then either he’s telling the truth and it’s not a problem, or you’ve gotten him to lie to your face.
If you can have the conversation with witnesses (I don’t know enough about what you’re doing to know how you’d do that) then it would look bad for him if he said he wasn’t interested and then immediately turned around and did the opposite of what he indicated. Meanwhile, you’re just trying to operate in the spirit of transparency for the good of the organization.
Ultimately, if this situation is going to be decided by naked factionalism regardless, then you’re probably not going to outmaneuver him. Frankly, that doesn’t speak well to the future of the org. If, however, the people there are actually interested in doing the work and not the factional nonsense (or at least if they don’t want to be associated with factional nonsense) then they probably won’t be impressed with someone operating in obvious bad faith.
Take with a grain of salt, I could be reading the situation way wrong.
If he says yes, you have your answer and you can work from there, maybe even indicating that you’d be willing to step aside if he’s willing to be an adult about it and have a conversation about your ongoing participation in the org
Thanks for this answer, it reaffirms the most likely path I've been considering which is that if he does eventually come out and explicitly express interest in my position, I think the best thing to do for all parties involved is for me to not compete against him and support him in his endeavours
split the org