Is it haram to follow the fatwas of contexualist/modernist scholars?

Is it haram to follow the fatwas of contexualist/modernist scholars? Is contexualisation allowed when interpreting verses? One example is Khaled Abou El Fadl who issued a fatwa some years ago saying that Muslim women in the West do not have to wear the hijab. Is he being sinful, or can you follow this? If you follow this, are you being sinful? But would you regard him as a scholar, does he have the ability to say stuff like this? I've seen stuff that mentions contexualisation. Like the Sword Verse (9:5). Groups like ISIS take the literal meaning to commit such acts, but we know that this is meant for the Arabs at the time? There also have been fatwas issued for European Muslims during Ramadan when the number of fasting hours have been quite long, that they may break their fast earlier. But some people within these communities disagree and fast for the all of the long hours. I am asking whether or not it is haram to follow such fatwas, as I am unsure about the validity of such things. Some scholars agree, lots of scholars disagree. As normal people we don't have the ability to interpret these kind of things correctly, so when two different groups of 'scholars' issue fatwas that are contradictory, it leads to a state of confusion. They can both be compelling but which one is correct? This is why I'm asking the question.