Higher ground sorting of Tyrannosaurs

Dr. Elizabeth Mitchell at Answers in Genesis recently published an article about the find of a Tyrannosaur, Lythronax argestes.  She also dealt with the higher ground sorting idea.  I just had  couple of thoughts.

"Such a scenario begs the question of what common ancestor these different twigs on the dinosaur family tree branched off of as well as what prompted them to evolve similar features along separate paths."

Since Answers in Genesis considers Tyrannosauroidea to all be the same "kind", don't you agree with that statement?

"But these fluctuating water levels would also have temporarily isolated sections of land where some animals could have found a brief refuge, ultimately being overwhelmed to produce more layers of fossils that evolutionary paleontologists now interpret as landmasses isolated for millions of years."

So the explanation for why Tyrannosauroidea is only found in the Jurassic and Cretaceous sediments in Europe, North America, and Asia is that they coincidentally were isolated on these refuges that would become three separate continents. Honestly what are the odds? It seems to make more sense that instead of Tyrannosaurs of all sorts of different species coincidentally being isolated on three continents during a period of weeks, that the Tyrannosaurs actually lived chronologically later than paleozoic animals.

Also where were the isolated zones? This Tyrannosaur was not buried where it died in a flood model. Beneath the fossil are tons of sediment that were all supposedly deposited in the beginning of the flood week and did not exist before the flood began.