It is correct that the original mistake was made in 2022, but according to the community note (hopefully Musk doesn’t delete it for speaking out against DOGE), the claim of $8 billion linked back to the already revised contract saying $8 million.
In addition, they apparently corrected other errors (and only those errors and not other things that were likely impacted by the same methodology flaws) called out by this anonymous x user, but did not change the overall $55 billion number.