100% you should create a viewmodel that comprises of the two models you need.
public class MainViewModel
{
public ModelA ModelA { get; set; }
public ModelB ModelB { get; set; }
}
You should keep the association of one view -> one viewmodel class. I keep to this in my MVC apps, and it helps me keep the views simpler.
I would never try to mix two viewmodels in one view; that's making things tricker for yourself.