You can try alt tabbing to the trainer to activate it and the options to see if sound comes back. Some apps are allowed to take complete control over the sound card and this game might be one of them.
But I did download the Gamepass trainer. And it worked perfectly before the March 11 Patch for the Gamepass version. After the Gamepass update, the game crashes to desktop shortly after the Trainer has been activated.
I already got an email saying my request was denied, but the crashing is definitely happening after the Gamepass March 11 Patch, while the trainer worked fine before the patch. I guess I can try downloading the trainer again, but I did that yesterday after the Gamepass patch was released and it still crashed.
I redownloaded the Gamepass trainer for a 3rd time, and the game still crashes shortly after activation. Not immediately, but probably around 45 seconds to 1 minute or so after.
[Edited by jrcbandit, 3/12/2020 6:43:48 PM]