I realise this isn't massively helpful, but I can confirm that my changes (for example to the weapon group selection) have taken just fine.
Some things to try:
Make sure you have the latest VA.
After installing the update, exit and restart VA.
After making the changes exit and restart VA.
Make sure it's set to use "English - Custom" as your voice trigger set and not just "English"
Outside of that, you'll need to consult with their forums or discord. Be aware that for their discord support isn't 24/7 and you need to catch someone online, but they are pretty helpful usually.