If you take the reproductive rate of alligators or Komodo dragons as a ballpark estimate, how many generations do you think would occur in, say, 30 million years? How many generations do you suppose it takes to get a teacup poodle from a line of wolves, or from a pack of mongrel dogs?
30 million years would only apply if the mutations waited that long. When do the modified T Rex skulls appear in the timeline? At the beginning of the T Rex species, middle, or at extinction?