> Did those fossils have a date stamped on them, who says they're a million years old.
Geologists, biologists and physicists. When distinct braches of the physical sciences all largely agree that the age of a fossils is "X million years old, plus or minus some small fraction," it's interesting that they are to be doubted because some vaguely written, non-peer-reviewed ancient text says something different.
Use the same underlying method and the results will be around the same figure. Once that underlying method is successfully challenged it throws all of the previous assumptions into chaos until order is restored, based on a "new" general assumption. The real question is whether the general assumption by the different disciplines of science you mention is valid.