Consider, when one makes comments such as this "Why would a humanist care what Baha'u'llah thinks about anything?". It means that one was not interested in the first place, justice was not being pursued.
You didn't answer the question. Did you consider it rhetorical? It wasn't. You keep bringing citations to unbelievers. I'm wondering why. No, I'm not interested, and will remain uninterested if you can't give me a reason to be. With all due respect, I don't trust your judgment of what is wise or what constitutes justice, and wouldn't read anything based on nothing more specific from you than that it is truth and wisdom from the most high pen. That's not an endorsement.
Also, your religion has disqualified itself with humanists as an arbiter of justice. That's the price it pays for its homophobic doctrine. Rational ethics declares that idea immoral, because it is irrational (faith-based and lacking empirical support) and destructive. You don't need to ever address that - none of you have, none have tried to argue that it is not that - but the faith is sullied by it the way the Catholics were by the priest scandal. They also do the best to mitigate the damage, but nobody is forgiving them but themselves, just like the Baha'i.
Surely you have something to offer original to your faith that is evidence of its worth as a source of wisdom and moral guidance if you say that it is that. How about an original (not found in earlier writings) moral principle that has borne fruit and is worthy of a humanist to adopt. If you have no such thing to offer, what do you suggest I conclude, given that I am pretty sure that if you did, you would be proud to present it?
I ask the Christians the same regarding Jesus, and get crickets. It's a very revealing question. There is no moral idea from Jesus that is original and worth retaining. Like what? Finding somebody sexually attractive is adultery? That there are times when plucking out an eye or cutting off a hand is proper? Are either of those original to Jesus? Either way, they're bad ideas, and disqualify the Gospels as a source of moral instruction. How about your faith? Can Baha'u'llah outperform Jesus in this department?
Can there be unity when one side, the atheists, can't compromise on their beliefs?
What do you want compromised? Humanists are already maximally tolerant of everything but intolerance, and that's not open for negotiation. Did you want them to compromise their moral intuitions and accept or partially accept Baha'i homophobic doctrine? Why would they? That doctrine is immoral by the standards of rational ethics.
Somebody asked recently about compromising with the anti-abortionists. They may be able to impose their values on humanists, but why should humanists ever accept that or move closer to that ideologically? Humanists advocate choice, which is a form of freedom and tolerance. The anti-abortionists advocate forced birth, which is the opposite, and a dangerous state of affairs for women.
We don't compromise on ethics, and neither do you. Or maybe you'd like to modify Baha'i doctrine and accept a compromise position on homosexuality, like it's OK if confined to a monogamous marriage. That sounds like a midway point between the two positions. What do you say to a compromise?
We are critical of immoral beliefs, especially those that a person adopts through lack of religion.
As you can see, humanist are also critical of immoral beliefs, although they apparently have a different idea of how that is decided than the faithful. I am aware of no moral precept of any religion in conflict with any humanist precept that deserves to be called moral. Religions are not a good source of moral imperatives, so I have to conclude the opposite of the last part of your comment. Nothing from moralistic religions, thank you.