I recommend reading this 2019 interview with the former mayor of Munich who introduced LiMux with his party in the early 2010s (use a translator like DeepL or so if you don't speak German):
https://www.golem.de/news/von-microsoft-zu-linux-und-zurueck-es-gab-bei-limux-keine-unloesbaren-probleme-1911-144917.html

Excerpt of the part where he talks about Microsoft's attempts to turn them back to using their products:

Soul massage from Steve Ballmer and Bill Gates

The most intense experience I personally had was a visit from Steve Ballmer, Vice President of Microsoft. He interrupted his skiing vacation in Switzerland to visit me. With his well-known enthusiasm, with which he dynamically jumps around on stage at conferences, he jumped around in my office and first praised the beauty of Munich. But then he said that I was faced with a catastrophically bad decision that I could never justify to anyone, especially not to taxpayers.

Funnily enough, he kept making new financial offers during the conversation about what else Microsoft could add, for the school department for example. They kept offering a million and another million and another million and later a dozen million cheaper than before. That's how important the renegade state capital of Munich, perceived internationally as an IT stronghold, was to Microsoft as a symbol.

Would it show a way forward or return to the Microsoft bosom in repentance? We have calculated that Ballmer has improved the financial offer by around 35 percent. But since we wanted to make a strategic decision and not just a price comparison, this was not significant.

Linux-Magazin: Bill Gates also came to visit?

Christian Ude: He was in Munich for a presentation of the House of the Future, which he was really enthusiastic about. He was able to control from his car how high the room temperature should be in each room and whether the fridge should defrost a little. On his way back to the airport, I had the opportunity to talk to him. So I was sitting with one of the richest men in the world in a camouflaged van that was luxuriously equipped on the inside but looked from the outside as if it belonged to a small craft business. Gates asked me, stunned: "Why are you doing this? That's absurd! I can't understand it at all!

Since I'm not the hard-nosed IT specialist who would be a match for Bill Gates on every detail, I simply said: "Please note that we are concerned with independence. We don't want to be dependent." Then he said: "What nonsense, dependent on whom?" "Because you're already there: On you, of course!" That really made him fall apart and he said: "It's incomprehensible to me, it's ideology."

So Microsoft has really used every form of soul massage from galloping price reductions during a single meeting to the use of megastar Bill Gates. But I have remained firm. I didn't discover or develop Linux for Munich. But I did take responsibility for it. But it wasn't about me, it was about a piece of municipal independence.

A politician has to live with and learn to deal with the fact that there are people who understand an incredible amount more about a specific topic than you do, but who work for companies or groups and are therefore naked lobbyists. Should such interested parties be the main source of advice? I mean, it was no coincidence that Suse and IBM were very positive about Limux because they also work with open source. Microsoft was extremely negative, as I was able to experience for myself. Both sides certainly understand a great deal about IT, but the insights they proclaimed were driven by their own interests.

In a TV documentary last year, I heard that the influence exerted in the city of Vienna and in the Italian Ministry of Defense was no less massive and that Microsoft was determined at all costs to prevent an alternative from proving itself anywhere in Europe. In any case, we in Munich wanted to become independent by 2014.