If I remember correctly, wasn't there no evidence in scientific papers etc that the virus RaTG13, which is the closest known relative to SARS-CoV-2, actually existed until after the Covid pandemic started and they suddenly published information about it?
However, the evidence is pretty clear that this was found and published earlier. It was originally described as "BtCoV/4991" and it was described and published as far as I can find as far back as 2016. (The name was changed to RaTG13 to describe that it was collected in 2013 in Tongguan).
https://www.ncbi.nlm.nih.gov/nuccore/983856042 <-- partial RaTG13 sequence in 2016