This is an old security update. It released on Mar 29, 2018.
As I said there is no any security update for Sierra at Apr 24, 2018, you can see the all update list in this link;
Unfortunately, removing the THB cable isn't working with the ASRock MB, no TB devices show up at all...
When I had the gigabyte Gaming 7 Pro and was waiting for the connector adapter (GB uses a different header pitch: 2mm vs 2.54mm) no TB devices were seen in macos either...
Ok so I was having issues with on-board and HDMI audio using VoodooHDA. No AppleALC due to AMD setup. VoodooHDA was crackling on on-board and couldn't sort and there was no HDMI output. So I bought a Sabarent AU-MMSA USB Audio device. Issue is it's acting just like the on-board audio was. With or without VoodooHDA being injected.