Ah yeah, you got me. Though I don't really count that as good evidence for an actual "redemption" since it apparently was burning Tethers that came from Bitfinex: https://www.coindesk.com/tether-just-burned-500-million-usdt...

And since Bitfinex is the owner of Tether Ltd., there is unfortunately no outsider that could credibly confirm to have actually received any USD in exchange for those burned Tethers. Bitfinex might just as well have sold Bitcoins from its own stash (or from customer wallets) to others for USDT and then burned those USDT in order to stabilize the USDT/USD price which wasn’t exactly holding up well at that time. If they had actually printed more USDT than they have USD in the past, this would be a smart move in order to distribute the "missing" funds more evenly across multiple crypto coins in their custody, which makes it less likely for them to run out of one of them and thus makes it less likely for the alleged scam to come to light.