What is the current opinion in scholarship about the Hellenocentrism of the sources that recorded the events happening after the death Alexandros III of Makedonia, The Great King, the King of Kings, King of the Four Corners of the World?

I say this because the sources seem to say offhandedly about the daughter of Artaxerxes III, about the daughter of Dareios III, and about Amastris, the niece of Dareios III.

It is logical that their roles are downplayed, but even so, the only use of royal purple recorded in the sources is done by Krateros. It is also recorded that Phila used the royal purple in 317 BCE or so. Anyone with some knowledge of the marriages of the age might see where I am going.

For starters, it seems that Perdikkas and Roxanne conspired to have murdered these Persian brides of Alexandros. I read it somewhere that one of them might be pregnant and that's why they acted? After all, Roxanne herself was pregnant, so hardly her son would be above the other one in the succession.

Roxanne's marriage was done in a moment of great need. Alexandros needed the marriage to get a loyal following of powerful lords of the Upper Satrapies, at the very least enough to get a great part or at least significant enough faction on his side to have a hope at conquering the rest. I am aware that maybe the fact that Alexandros later married these daughters of the two last kings of the Achaemenid line might be the reason behind the revolt of Spitamenes. This in itself might have prompted the massive wedding to definitely tie fortunes together.

So like this, I also see that Krateros was essentially married to the last heir of the Achaemenid line, Roxanne might have been considered a traitor, and so was Perdikkas. Since we know these things from tertiary sources (Roman sources commenting on Hellenistic sources commenting on the witnesses such as Ptolemy, Aristobolus, Hieronymos, etc) it might be something got lost on the way. After all, the Alexandros told in Roman sources is a moral telling many if not most of the times, so to reduce it to a noble infighting instead of crimes of murder and one party not accepting the charges is plausible or am I looking too much into it?

So this is the thing: How trustworthy is the Roman historiography that we can assure they did not slip up on these details such as Krateros marrying Amastris and then Amastris marrying the Tyrant of Herakleia Pontika and Krateros marrying Phila who would later marry Demetrios, how curious the first family to declare themselves kings? And I am aware of them winning and not being any more royals around, but maybe being royal was also a condition for allowing the army to claim which party they support, though that is a foregone conclusion (I mean, it is their army, how not to support them?) my point is that, the reliability of Roman sources hating all Orientalism. Only Diodoros strikes me as honest and honesty does not mean providence foresight, so...