Alright, so gave it look over I'm fixing up grammar issues. As for why he has three Master's listed.

Master Vorlya Sisk is a very recent promotion to Master, I thought about listing her as a Knight still in some of the reports to have that come across but I was unsure if that would sound like I forgetting to keep her rank the same or if the intention would be clear.

Master Turus is a very elderly Master and one he reached the position very late in life through wisdom and understanding the force through meditation.

Master Sar Dan'ii was a Battlemaster and well-respected teacher on Coruscant who took in promising saber combatants as her student usually.

As for his survival of the battle of Coruscant, he and his master were believed dead at first. Airus was found when they moved to search the ruins of the temple in lower sections. They were not at the temple when the attack began instead were heading for the starport instead of returning to the temple they left it his Master believing it would fall.

He had and his master had survived in the initial attack, they retreated to the lower levels his Master wanted to organize survivors and strike back. 

Before they could do anything a single Sith Lord who had pursued them dropped down. Airus's Master had already been wounded so he disobeyed her choosing to stand at her side rather than go try to find others. Airus was thrown aside into a pile of stone rubble, his master killed by this Sith while he lay injured and unable to move.

I was thinking the details of his survival would be something kept rather secret.

As for his age. Well, he joined the order at age two, served as initiate until twelve he was originally slated to has his promotion at twenty after the battle of Coruscant they delayed that and served further as a Padawan until age twenty-two under a different Master. So he served as Knight for six years currently.

Either way, I'm working on edits now. Hope this isn't too much.