A: - the clue has about the same value as most of them, there is no absolute proof that Waltz ever said it, nor conclusive proof that he did not. It may have been one that is true and yet "fuzzy" enough that he felt no danger that others might find his mine by that information, like the part about the old Military Trail.
B: -the problem is that there are a number of locations where the four peaks of Four Peaks APPEAR to line up; in fact they never do line up and cannot, as you can see on a topo map they are not in a straight line. It is deceptive to look at this by satellite imagery, remember the men of Jacob Waltz's day could not even fly ten feet off the ground, landmarks visible from the ground are what they worked from not any birds-eye view. Anyway there are at least two spots to the SW of the peaks, a good sized area to the SE, an area to the NE in the Sierra Anchas etc where the peaks APPEAR to line up well even though in reality you are only able to see two or three of the peaks lining up, the other peaks are not visible due to elevations involved.
C - there is no other 4 Peaks in Arizona as far as I know, though there are several Sombrero Peak/Butte/Mountain-s in southern Arizona alone. Also there are several "pointed peaks" just in the Superstitions, which could be the pointed peak mentioned in clues, Waltz never stated it was specifically Weaver's Needle.
When/if you go to the area you will see how different things look from ground level, than from satellite views. The view from overhead distorts the impression, especially in how steep things are, but also trails can look like stream beds, boulders like bushes etc; the three Utah men were apparently deceived by a stream bed they took to be a trail, which must have been a very difficult hike for them, and they ended up dead. Don't depend on Google Earth to judge what that terrain is really like.
I hope this is of some help, good luck and good hunting amigo I hope you find the treasures that you seek.
Oroblanco