Why Trump used go betweens to collude with Russia during the election

Why did Trump use so many go betweens to meet with Russia during the 2016 election? Obviously it was to not get caught, but there is another reason, The Secret Service. I am not saying that the Secret Service was used to spy on Donald Trump during the election because that is not their job. The Secret Service is to protect the candidate and to be tasked with carrying out surveillance at the same time would take away from the primary job of protecting the candidate. That being said, I don't think anyone colluding with a foreign government to subvert an election is going to meet with that government in front of a Secret Service agent or behind a closed door guarded by a secret service agent. So how do you get around it? Use go betweens. But which go betweens? We know that people involved with his campaigns and his sons but did he use others? If the truth be known, which I hope comes out soon, Trump used business associates and members of his Organization to interact with Russian intelligence and other Russian agents. I am sure he sent his people in the guise of doing business to work with Russia. He may have used his people to meet with Russian intelligence while they were conducting business in other countries or inspecting his properties. I bet if you compared his company's travel accounts and bounced them of the travels of known Russian assets you will see a large number of coincidences of both being in the same place at the same time. I am sure there would be overlaps in stays to try and avoid suspicions but it is obvious they are connected. If you want to really connect Trump with Russia and collusion then bounce his families' and trusted employees travels to the travels of influential Russians and assets.
Now let us consider another Trump asset to communicate with Russian intelligence. Trump's private jet. What communications to Russian assets took place on his jet? What is the setup of communication equipment of his jet? Since he likes to stay in contact during his travels he probably has a good communication and information system on his jet. A system that uses crypto to ensure privacy? I am certain of it.
We are just seeing the tip of the iceberg when it comes to the ways Trump secretly communicated with Russian assets. When the complete story is out there it will reveal an iceberg bigger than the one that sank the Titanic, one that will hopefully sink the Trump administration and the Republicans who decided to voyage on the Trumptanic ( of Russian registry). Who will be caught without a life jacket?