Here I want to change the topic and touch upon another important mission of the colony, not discussed before.
Next important mission of the colony is education of human interpreters-facilitators. I will name them interpreters for short. Obviously, many aliens have no problem speaking human languages audibly or telepathically. The problem is that most aliens have non-human appearance and typically have a strong alien accent.
When you speak to our politicians, don't be surprised that they are not cooperative enough:
1. They are very secretive and deception is part of their work. They are scared to death that you can read their minds. Using a human interpreter and avoiding telepathic contact would greatly improve the trust, because the politicians will fear you less and this will make them much more comfortable. It is respectful and polite to not enter human mind without explicit permission and good will from the human.
2. The politicians are justifiably afraid of assassination by humans for talking to you and especially for cooperating with you. Using a human interpreter, especially kind, motherly, non-threatening women as interpreters will greatly soften this fear. Also I recommend using human-looking, kind and loving alien females and elders in negotiations. This will also greatly soften the fear. I recommend studying the role of female politicians in recent human history. I recommend researching the biography of Golda Meir. Elderly women politicians are very powerful in politics of peace since they are less competitive, less aggressive and more trusted than men.
The interpreters-facilitators can be recruited among earth humans and trained to work interpreting aliens. Human colony will give plenty of opportunities for the interpreters to learn their skill by introducing new human members of the colony to aliens. The tour bureau of the colony could use interpreters to guide and facilitate the tours of humans to other galactic locations. The earth politicians would trust better the interpreters which come from their culture, their country and their social level. Military would trust interpreters who are from their circles and politicians would trust people speaking their language. Again, I would strongly recommend using females as interpreters-facilitators. This is traditional to earth and makes sense. Among females, naturally, you would need to choose those who are talented in facilitation, that is who don't contaminate negotiations with their own opinion, at least not visibly. Obviously good facilitators have their own agenda and are capable of strongly influencing the process of negotiations. So you would need to choose the facilitators which agree with you on major principles. Even with my limited experience, I know a couple of people who would make great facilitators. Realize of course that not only humans would need interpretation of what the aliens are communicating but also the aliens would need interpretation of what human politicians are saying. In human politics much is implied without pronouncing it. Much is read between the lines. If you study military reports and communications, you would be puzzled by omissions. I know this mostly by reports by military whistle blowers on YouTube. It is amazing how much is omitted. The main art of their communication is to deliver the information to the listener without actually pronouncing it. It is very cryptic and resembles telepathy; another goal of their communication is to avoid revealing any extra information which is unnecessary for delivering the main point. This is also very cryptic. Among Soviet leaders, Gorbachev was notorious for speaking and actually delivering information while not naming names and avoiding spilling extra information. The same can be said about many public relations specialists. One of the roles of the facilitators would be to interpret these very cryptic responses of human politicians for alien negotiators.
I will tell you about my experience relevant to the question. In old times, in 1980s, I was listening to Radio Liberty and Radio America trying to figure out what is wrong in Soviet Union and what was happening outside. Initially, I was very suspicious about what they said because Soviet propaganda often referred to these transmissions as lies and warned the citizens about listening to foreign propaganda. Initially, for me it was inconceivable that Soviet people would become disloyal to their motherland, leave the country (which was close to impossible) and start working for foreign radio stations broadcasting propaganda to Russia. As I said, the accent of the people working on these stations did matter. Broadcasters in Radio Free Europe, Radio America and Asian stations had strong foreign accents. These could be dismissed as foreigners. The news they broadcasted were also quite irrelevant to us. On the other hand, Radio Liberty and BBC people typically had no accent and spoke on the topics which were relevant to us. After much listening, I realized that these were Russian dissidents who were deported from the country by KGB or succeeded in escaping. Later, I learned that Alexander Galich, most respected by me of all dissidents, also worked on Radio Liberty until his assassination.
As I learned that these were former Soviet people who spoke to us from the other side and explained what is wrong with us and how it is in the free world, only then did I take their words seriously and start to relate to them, giving them much weight in my perception. I hope you see the similarity with the current situation. The human colony on your side, humans who can be friends with you, who support your policy, human interpreters who work with you, will be your best argument. These people will know you closely and will be able to report back to earth how it is out there in your worlds. The interpreters-facilitators will be the first people to help the humans and human politicians to relate to you and consider trusting you.