shein: HASHEM decrees that what the Rabbonim determine is the will of Hashem. And a lone authority does not qualify as the consensus of the Rabbonim. You have yet to identify this authority, by the way.
And how does the fact that the owners of the bus go with this authority make him the arbiter of the will of Hashem any more than any other Rav?
L’tachlis, though, arguing about Hashem’s will is irrelevant to this thread. There is no way you can unilaterally assert that Hashem wills us to enforce separate seating on public transportation. And that is the matziv.