[Der-Ubermensch]

Hello guys, I need your help on an exercise. I have to write the mechanism of hydroesterification of styrene. In the exercise they gave me the complex  : [(dippe)Ni(PhCHCH2)], CO, MeOH and a styrene. So, for me, the complex got 16 electrons because dippe and styrene are L ligands, and Ni° = 10 electrons. In the first step of the mechanism they said that the oxidation state of my complex is changed by 2 units. So that means that 2 ligands X are added on my Nickel. But I don't know which ligands are linked to my nickel. Is that styrene ?

Thank you for your help (sorry for my English, not my first language).