These are not following the explicit covenant. There is only one Baha'i Faith that has valid leadership according to the covenant. All of the Baha'is are entitled to believe what they want about the teachings, but they are not entitled to try to usurp the leadership of the Baha'i Faith. This is different from all other religions, where there is no explicit leadership established by the founder of the faith, and within each division independence of thought is discouraged.
May I ask some questions about the Baha'i Covenant?
Who are the parties in this covenant? Individual Baha'i believers and God?
There seem to be a greater and a lesser covenant. Is this like the Laws of Moses as compared to the Laws of Noah? Which laws are part of the lesser one, and which are part of the greater one?
I understand that "breaking the covenant" is a grave matter in the Baha'i Faith. What does it mean, in terms of what offense is being committed?
Is it possible to break the greater but not the lesser covenant?
Are the consequences really excommunication?