Why Kocharyan does not participate in Armen Sargsyan's inauguration?

Today it was announced that the second president of RA Robert Kocharyan won’t be present in the inauguration ceremony of the fourth president of Armenia Armen Sargsyan on April 9. They said the reason is the tense relations between Kocharyan and Armen Sargsyan’s close friend British-Armenian businessman and benefactor Vache Manukyan. Everything started after the conversation on luxury ship, which Vache Manukyan anchored in Monte Carlo in the early 2000s. What did they talk, no one knows but after that their relationships have frozen.