[Kuruharan]

Sorry, but I think Morgoth could have gotten the information out of Hurin quite easily

Then I am afraid that you are missing the point of the entire episode. Hurin's defiance centers around his refusal to tell Morgoth about the location of Gondolin. This is what makes Hurin's actions at the end so tragic because it renders futile the decades of defiance of Morgoth.

There must also be understanding of what the defiance of Morgoth was. It was more than just Hurin's taunts over the course of ten minutes. It was his refusal to speak to Morgoth of the location of Gondolin for thirty years. His silence was part of his defiance.

I am afraid that you are quite wrong about the ease of getting information out of Hurin. Hurin earned his nickname of "Steadfast." Aside from killing there was little else that Morgoth could do to him, and Hurin still would not break.

If he wanted to find out more about Gondolin I'm sure he could, as the most powerful being in Arda, have found an easy way to get the information.

Morwen already capably answered this, but there is something that I will give a little more detail to.

It is evident from some places in the stories that Morgoth still had some of his ESP (for lack of a better word). Note his speech to Mablung at Nargothrond, and the various places in the texts where it says that Morgoth knew more about the deeds and plans of his enemies than was commonly thought.

However, his ability to do this seems to rely on (to some extent) other knowledge of the situation. In other words I think that he had to have somebody there on the ground for him to have knowledge of the situation. I have always believed that there was a little bit of Morgoth in all his servants, and that he kept in touch with these little bits of himself for command/intelligence purposes.

So, since none of his servants could get near Gondolin there was no way that he could find out much about it himself.

he wanted to humiliate him, & by extension his enemies

That is certainly true.