Qt has multiple levels of verbosity for logging. If you are able to print qInfo() messages but qDebug() is not outputting anything, you need to turn on the debug messages.
qInfo() << "Is this working?";
qDebug() << "but not this?";
You can set the Qt logging levels in ~/.config/QtProject/qtlogging.ini like this:
*.debug=true # Enable all debug messages
qt.*.debug=false # Disable qt debug messages, leaving only ours