Are flatheads the Same as tabby’s?
I haven't ever heard of them referred to as tabby's around here, but did a quick check and it looks like they are the same fish, just different regional names:
"No fish better typifies the storied history of angling in Mississippi than the catfish, and no catfish more so than the most mystifying member of the species -- the flathead.
You may know it as the "tabby cat" or "yellow catfish," or any of the other scores of nicknames given the fish. It's a beautiful fish, but also odd -- odd to the point of ugliness."
https://www.gameandfishmag.com/editorial/fishing_catfish-fishing_ms_0508_02/242064