It’s funny that Garrett gets blamed for bringing Linehan in but no credit for Moore. Fans.
In the case of Linehan. Jerry told Garrett that he was no longer calling plays and was no longer to be the OC. So go find an OC that you are comfortable with. Garrett hand picked Linehan. Linehan actually did a good job in the beginning. Improved the Cowboys offense, added things to it that Garrett didn't do and added the power run game to the offense. Which is exactly what was needed.
In the case of Moore, Garrett announced publicly when asked about Linehan that "no major coaching changes would be made this year". Jones followed that up with publicly smacking down Garrett and saying publicly, "we haven't even met on that yet, I reserve the right to make that decision". Garrett is just a puppet. Does what he is told.
Now after the firing of Linehan did Garrett push for Moore being the OC? I would think he would have. He probably thought Moore was someone he could control.
Until Jerry was quoted as saying...………….."Moore, if your ideas aren't being implemented, let me know and I will make sure they are". All but letting Garrett know that Moore should be left alone to do his thing and run the offense. And that "Garrett will be a good safety net for Moore".
But who gets credit for Moore is really a side argument. What matters is that Moore is fixing the offense in ways that Linehan and Garrett could not. Moore is a much better coordinator than Garrett or Linehan. This offense is taking off because of Moore.