I wouldn't trust them either. Once being trapped and tricked in by them, you will have difficulties to either leave the country legally as you won't get your employer's permission to do so or change the employer. You will need the employer's consent for immigration to leave. How helpful would ADVETi be in this when you have a dispute re work or payment with them? Answer that question yourself...

Emiratis are natural liars and the most dishonest people you could ever meet!