>> Many Mississippi Black state politicians were in favour of the current flag <<
Yes, a few were in favor. But I don’t think it’s accurate to say there were “many.”
>> The flag was adopted almost unanimously in 1894 by black and white Mississippi politicians alike <<
Almost? After the adoption of the 1890 constitution, the Democrats were able to oust almost all blacks from the legislature, and by 1893 there were only three blacks left.