Dealing with politics in Agile organization

Hello, I am sure as a Scrum Master in a big organization, people had to deal with issues like I describe below.
I would really appreciate successful stories that give ideas on how to handle it.

The main issue to deal with is politics. The size of the organization is, a Scrum Master is a local person who deals with a Scrum Team only. The part of the Scrum Master promise to serve the Organization is done by a special office of Agile Advisers. A Scrum Master has little say since the Scrum Master duty is to educate the Scrum team(s) and local managers on the right Agile/Scrum practices and not tell managers what to do. Not all of the managers are within the reach of the local Scrum Master to educate.

Yes, the structure of the org includes having Teams managers, managers of those mangers and so on. So, one manager can have several Scrum Teams members under the manager.
As result of some change on the company level, the managers reporting structure was changed, and our department was joined to another one, which is located remotely. A need to learn about each department practices arose. As result, part of our two Scrum Teams members are traveling to the new Team's Site to learn about this new Teams, and give some info about our Teams.

- A decision on who will go to meet the new Teams/new management was made by our managers, and the result was just announced to the rest of the Scrum Teams. I believe there are two issues here: the discussion on the trip plans had to be done not just on the managers level, but both Scrum Teams had to be part of it. And, it should be the Scrum Teams who decides on who should go. I understand that managers are not part of any Scrum team. But the reality is, we do have managers, and they have more power than any Scrum Master. And as in any big company, politics do present. And I find that as a Scrum Master, I have to deal with politics, and just educating the managers on the right agile/Scrum practices is not enough.
Q: What would be suggested way of handling such situation?

- We do have Scrum Teams, where I educate that there are no developers vs QA people, there is one Team, where people have different functional roles. However, as part of the prep to the trip, a request came to provide a feedback on "what works well, what does not work well" to be provided by QA and developers separately. Such feedback was collected separately by representatives from QA and the developers who are visiting the other Site. As result, those Scrum Team members who are QA did not see the feedback provided by those who are developers. I believe it is transparency violation. I do not have any power to change that. Just educating my manager on the right way (from Scrum point of view) of handling it was over ruled by "That is the way we were asked to provide info, since the other Org has separate QA and Developers Teams"

Q: Happy to here any suggestions/successful stories on handling similar situations.