I am the wrong person to ask on the matter of Alexander's retinue, unfortunately. Events such as the siege of Tyre, or the storming of the Soghdian Rock are all quite well-documented, but the details are obscure to me; I pay more attention to the Iranian matters therein in the accounts, and details on the general cultural history. When it comes to obscure personalities, such as Alexander's chief engineer of siege-craft, all I can say is that the core of the artillery available to the Successor kingdoms, were all inherited from an extensive Achaemenid knowledge of siege-work, applied with a Graeco-Macedonian twist to the matter, by introducing arrow-projectors in addition to stone-throwers (Catapults), siege towers, battering rams and various sapping techniques. This knowledge by itself was not unique to the Persians at all; They merely refined it.

By and large, the Graeco-Macedonians basically inherited an ancient tradition which was brought to mastery already during the age of the Assyrian hegemony. Like the Achaemenids did it, the Successors merely refined and polished what already was available to them. A process which was inherited by the Romans, and later found an equal among the Sassanians. This doesn't exactly answer your question, but it provides a brief and generalized background in the availability of siege-craft. Hopefully this widened your horizons a bit.