I think what happened was that the "peace negotiations" went ok for Alex, but Kleiman then went back to Vadim and pointed out that the Mexicans who had blackmailed him into signing away his shipping interests in the drug smuggling were still in a position to shaft him and make him (Vadim) look bad to his "competitors". And pointed out that therefore Alex was still an enemy.
Realising (astutely) that Vadim is likely to go back on his word, Alex tries to introduce the Mexican cartel to Vadim, in the hope that getting them on the same side will save his (Alex's) skin.
It isn't clear who was responsible for the killing of Vadim's daughter: it wouldn't have been Alex's dad. But when he appears to realise what has happened to tried to warn Alex that he is in even more danger than before as he flies off to Moscow.
But too late: Alex's phone is already in flight mode ...