the answer to that question is a simple one and you should already know it. In as many world views as i can think of, individuals (in this case the scientists) only consider evidence valid when it supports the hypothesis...all else is discarded citing failure to prove the original theory.
You could not be more wrong.
The exact opposite is true in science.
First, to "test" a hypothesis in science, one does NOT try to support ones hypothesis. Instead, one tries to show it false.
Secondly, when a scientist publishes a hypothesis, his / her peers will jump on it like hawks to try and prove it wrong.
In science, fame and glory for scientists is reserved for those scientists who show their collegues to be WRONG.
There is NO fame and glory in science for upholding the status quo.
Nobody in science has ever received a Nobel (or any other kid of award) for providing support for a model and upholding the status quo.
I would not become famous in science for conducting the bazillionth experiment that supports evolution theory.
I would, however, become famous overnight and receive a nobel and all the grand money in the world if I would manage to disprove evolution theory.
I'ld have universities, streets, statues, etc named after me.
My name would resonate through the ages just like the names Darwin, Newton, Einstein, Farraday, Feinman, etc.
This idea that scientists conspire together and actively work together to uphold the status quo is probably one of the most giant misconceptions that the anti-science / creationist crowd hold.
So much so that it bears repeating:
fame and glory in science is reserved for those scientists who show their collegues to be WRONG
If there was only the SLIGHTEST possibility or hint that "all" dating mechanisms were incorrect, PLENTY of scientists would be working DAY AND NIGHT to show them wrong. It would literally be a RACE among them to be the first to manage to disprove them.