The fragments may or may not be fake (consensus seems to be that the poem is probably genuine), but the provenance was certainly covered up. See https://eidolon.pub/the-murky-provenance-of-the-newest-sapph.... It's all quite scandalous and is connected to the theft and sale of biblical papyri to the Museum of the Bible. See also https://www.theguardian.com/news/2020/jan/09/a-scandal-in-ox... and https://www.theguardian.com/uk-news/2020/apr/16/oxford-profe...