Wait, you are unable to exchange your UST because the exchange requires a withdrawal fee of 1 UST? That just does not make sense. Do you even know how exchanges work?
In order to exchange your UST, you need to deposit it on the exchange, so you do not have to worry about the withdrawal fee and minimum withdrawal amount.
UST has been on the crypto exchange since the beginning of May. And in order to withdraw it to another wallet from the exchange, the exchange requires a huge commission. So I am locked with UST on the crypto exchange forever - when placing a sell order for 1 USDT order, they don't execute it, and they don't allow to withdraw it to exchange it with other users