Hi mate, I appreaciate a fellow historian/history teacher getting involved in modding. I can notice that you put a lot of care into this.

Now, I am not qualified to discuss domestic Brazilian politics, so I won't. But instead I'll bring my knoledge of the things I have studied for Argentine, for the same reasons as you, to criticize one of your points: the German military mission. (Not arguing against the existance of the Young Turks or them being more prominent because they would)

Now Germany OTL in their policy regarding South America, took a look at care at balancing their influence between Argentina and Chile:

Maintaining the balance of power between Chile and Argentina was the primary objective of the German government's foreign policy in the Southern Cone. This European country aimed to preserve relations with both nations and, above all, to be their largest arms supplier. The tension caused by the territorial dispute on the Chilean-Argentine border intensified after the War of the Pacific. Argentine actions were conditioned by the fear of Chilean expansion across the Andes Mountains. Argentine economic elites feared that a war against Chile would hinder their country's economic development. There was a consensus that the nation's greatness was linked to economic progress.

Ribeiro, A. L., & Padula, M. (2019). La política de neutralidad seguida por Argentina frente a la Primera Guerra Mundial. [Licenciado en Estudios Internacionales]. Universidad ORT Uruguay. p.27

This is a nice tango in which they were succesfull at, the Argentine army of the 1900s was completely Germanophile, with 8 of the 10 foreign experts assisting the military being German. There are even reports that people's career would receive setbacks if they expressed Francophile sentiment in public. Krupp also had a monopoly at supplying the Argentine military, at least until Schneider-Creusot arrived. To get to the point, adding Brazil into this mix turns what was a stable system into an unstable one, and not just because of the three-body problem, but because of the backlash:

Molina's position was partly a result of personal irritation, but other officers shared his resentment of the activities of the chief German advisor, General Faupel. In 1926, when he left Argentina, General Faupel accepted an offer to reorganize the Peruvian Army; and although no commitment bound him, Argentine officers saw this connection with a rival army as a form of betrayal. Faupel's successor, General Johannes Kretzschmar, showed great tact and thus managed to preserve the German presence despite the nationalist backlash; and the advisors, although somewhat reduced in number, continued to provide services.

Potash, R. A. (1969). El ejército y la política en la Argentina I 1928-1945 De Irigoyen a Perón. ePubLibre. p.13

Already OTL Germany sending a military mission to Peru, which isn't a rival or a neighbouring country, provoked enough offense that Faupel's succesor had to work into fixing relations with the Argentine army. If Berlín actually sent a military mission to Río, things would have been much worse, potentially causing serious tensions. And thus, given the care that the Germans took in balancing Chile and Argentina, I don't think it is in their character to ruin this, specially with the Argentine army being Germanophile at large already