In my alternate setting, I removed the "interference with mundanes" clause. That doesn't make it okay to go nuts because you still have the "bring harm to the Order" clause so it just makes it more grey. However, the whole Oath thing is definitely a no-no. Magi may be more involved with nobility and they have taken the field with no sanctions but a straight up oath, service as a court wizard, is not allowed. The whole Court Wizard role is taken by less-powerful Hermetics who are not Order members or by Learned Magicians. The setting is Harn so there are more practitioners of both arts out there and its a bit more high fantasy.
I did create a group of magi who entered into the Crusades though. They're slowly becoming an actual organization known as the Knights of Saint Nerius and have a small castle in the lands of the Crusade. But I reasoned it differently... they swore no oaths to the Pope or mundane institution, they swore them to God. Here are the Code Rulings:
Grand Tribunal, 618 TR
Remnas Ex Miscellanea brought charges against the magi known as The Nine Staves of the Pontiff. He alleged that their assistance to the Church in waging war and embarking on Crusade in the Levant area had endangered the Order by revealing their powers, engendering hatred amongst the local cabals and unacceptable interference with mundanes. He also cited that they were in violation of the prohibition against oaths of fealty to mundane authorities. The Grand Tribunal was unable to obtain a decision on the matter due to statements from the individuals indicating that their oaths were to a divine overlord, not the Pontiff, and that Rollas’ accusation extended unlawful immunity to non-Order members. The Nine Staves were also able to point to the expansion of new territories for the Order through their works. The Grand Tribunal ruled that, since no oath was given to the Pontiff, and that the magi had prosecuted their Crusade for divine and personal reasons against non-Order practitioners, that no violations of the Code had occurred.
Grand Tribunal, 651 TR
Charges were brought by the Quaesitores regarding the establishment of the Knights of Saint Nerius, a proposed fighting order within the Church. The founding members of the order were all magi of the Order of Hermes and, it was argued, that their oath to the Church was in violation of the Code. The Knights of Saint Nerius were ably defended by Kestor ex Guernicus, a member of the Nerians, who proved that there were no oaths to the Pontiff, only to God and the Church as a whole. Kestor was able to show that, on several occasions, the order had not accepted orders from mundane authorities and Church officers on the grounds that they violated the order’s precepts or Code of Hermes. That the Knights of Saint Nerius had not petitioned to the Pontiff for recognition of their Rule and Code and, therefore, they were no different than any other mystery or gathering that existed within the Order of Hermes for pursuing similar ends. The Grand Tribunal acquitted, citing the obvious risk of such a grouping, but accepting that many other cabals and conspiracies existed within the Order that were possessed of far more dubious means and motives. That the Knights of Saint Nerius swore, in their own personal faith, to uphold the image of Saint Nerius was deemed to be a boon to the image of the Order of Hermes at large.
Not sure if the sidestep would work in a strict Code environment but its good enough for me.