The truth about the deal which ended the missile crisis, from Dobrynin's perspective, is stated in his telegram. (Scroll down 2/3.) Writing the message as soon as he left the attorney general's office, he quotes Bobby Kennedy extensively. On the missile bases:
The USA government is determined to get rid of those bases - up to, in the extreme case, of bombing them, since, I repeat, they pose a great threat to the security of the USA. But in response to the bombing of these bases, in the course of which Soviet specialists might suffer, the Soviet government will undoubtedly respond with the same against us, somewhere in Europe. A real war will begin, in which millions of Americans and Russians will die. We want to avoid that any way we can, I'm sure that the government of the USSR has the same wish. However, taking time to find a way out is very risky.
Why is "taking time to find a way out" so risky? The attorney general comments about presidential advisors who were recommending a first strike:
...there are many unreasonable heads among the generals, and not only among the generals, who are "itching for a fight". The situation might get out of control, with irreversible consequences.
"And what about Turkey?" I asked R. Kennedy. "If that is the only obstacle to achieving the regulation I mentioned earlier, then the president doesn't see any insurmountable difficulties in resolving this issue," replied R. Kennedy. "The greatest difficulty for the president is the public discussion of the issue of Turkey."
Bobby explains why the President was so concerned about public disclosure:
In short, if such a decision were announced now it would seriously tear apart NATO.
Then, according to Dobrynin, Bobby gave the Soviet ambassador concession his government needed to hear:
"However, President Kennedy is ready to come to agree on that question with N.S. Khrushchev, too. I think that in order to withdraw these bases from Turkey," R. Kennedy said, "we need 4-5 months. This is the minimal amount of time necessary for the U.S. government to do this, taking into account the procedures that exist within the NATO framework."
Kennedy stressed the importance of secrecy:
"However, the president can't say anything public in this regard about Turkey," R. Kennedy said again. R. Kennedy then warned that his comments about Turkey are extremely confidential; besides him and his brother, only 2-3 people know about it in Washington.
When Dobrynin finished the secret telegram containing a possible end to the crisis, he did not have a direct, secure method to quickly send it to Moscow. Like most other folks of the time, he had to call a Western Union bicycle boy.