Came across this post while looking into this issue for our own deployment. The way I managed to work around was to run the service as an admin, which in turn runs the app as that admin. This is mentioned in another community post, but since this is unanswered and other people might end up on this page in the future, here's how to work around it and run the App as admin:
In our environment we try to use best practices and not sign into any computers with our admin accounts and use them only for doing administrative tasks, but on Windows 10 SupportAssist does not seem to give an option to run as an admin nor can I find the actual program path to run as an admin. Anybody know the path or steps to run this without needing to fully log on with an admin account?
SupportAssist run as admin