Bernie Madoff was also able to handle withdrawls from his fund to a limited extent prior to its collapse.

Also, are there entities redeeming USDT into USD? Or does it always involve intermediary crypto? (I am not actually familiar with the extent of cryptoexchanges out there that deal with fiat, so genuinely curious.)

Haha, what? Maybe if you're an institutional investor or whale (or another exchange is doing something for you), but for several years the closest thing Tether had to a redemption "policy" (beyond the fine print that said they had zero obligation to redeem) was:

* Only for holdings of over $30,000

* 90-180 day waiting period

* non-US nationals

It was so bad, that people put out bounties for anyone who could prove that Tether or Bitfinex (whatever, they're the same) had redeemed USDT. I believe one bounty was in the order of $5,000.

The ones I found were unclaimed.

that's a stupid thought