EYE- LUH is the American way of saying the Spanish word. Just like Uruguay is properly pronounced OO-ROO Y, but Americans  pronounce it YUR -A GAY.  if you have ever been to Austin, Texas there are plenty of Spanish words that got converted into a different pronunciation. The big one would be a main road name called Manchaca, which everyone pronounces "man-shack" instead of the Spanish pronunciation for the Mexican soldier it is named after, which is " Mun chuck-a"
Neither is incorrect, technically.  It depends on how you look at it, but Iss Luh was how the word was originally pronounced.