Keep in mind Neuro's try to rule out als not rule it in. They suspect als when it walks in the door. However even after a "dirty emg" they look for other things usally. That is why sometimes it can take awhile. Plus throw in the long lines at the clinics.
meaning if the fasciculation in that spot was caused by some disease there would be other things besides a fascicualiton such as fibrillations, sharp waves, odd recruitment patterns etc.
