It's probably a domain (as e.g. in Windows Domain, not DNS) setting that forces given phone to have a certain permissions before allowing integration with corpo

It's probably a domain (as e.g. in Windows Domain, not DNS) setting that forces given phone to have a certain permissions before allowing integration with corporate services (including email), but usually it doesn't have a way to discover a rooted phone. On the contrary you can disable other rules - like enforcement of PIN (if you know how) if you have a rooted phone.