I just wrapped up a miserable experience with AltMarket, the official home of TAO/XTO
I'm sorry you ran into this issue. I saw your post yesterday and talked to Bryce about it and my understanding is that he had to fire and replace a developer due at least in part to this problem and the lack of resolution.
One thing you didn't mention in your post is that he did send you your funds. They are still in mempool since BTC as we all know is only semi-functional when a lot of people are using it, but it seems like an important detail to leave out.
https://www.blockchain.com/btc/tx/48e2a924d20689c103b4d30e1a102bc6f3a526f7cdefb68b83f0002d43bd4cebNot cool that this happened with your withdrawal in the first place, but one positive is that the USD value is at least way up thanks to the Tetherpump.