Dark matter and the temperature of the universe

Factual Questions
1

Do the current theories around dark matter say anything about :

  1. How the currently measured universe temperature ( through background radiation) may not be correct ?

  2. The initial temperature of the universe (at the Big Bang) ?

  3. How temperature has decayed from the Big Bang to now ?

2

The accepted theory includes dark matter and dark energy and can accurately model the temperature back to a time very shortly after the big bang. The calculation is pretty easy back to about t = 300,000 years (we are currently at t = 13,800,000,000 years). Before that it gets more complicated, ultimately involving temperatures in the first fraction of a second that are so high that we do not understand the physics.