I believe the estimated age of the universe is only around 14 billion years.
My estimates came out to 18 billion years.
But that was based on kind of a guess - that the average density of the universe was about one proton mass per 10000 cc’s volume.
I was happy at least that it was in the ballpark!
You are correct. That’s why the 49 billion years sounded odd.
From Wiki:
The age of the universe is the time elapsed since the Big Bang posited by the most widely accepted scientific model of cosmology. The best current estimate of the age of the universe is 13.75 ± 0.13 billion years[1][2] (4.336 x 1017 seconds in SI units, or 13.75 Gigayears) within the Lambda-CDM concordance model.[3]