Normally Vince didn't like to get his hands dirty anymore but having his son's toy within reach was too good of an opportunity to pass up. He wanted to see for himself what was so good about her to keep his son around for so long.
As much as Luca tried to ignore what made him an alpha, Vince always thought that he got his taste in women from him.
The driver who kidnapped Sophia had directions for a hotel he was meant to bring her to. It was a run-down love hotel filled with as many hookers as roaches. A lot of the mob's business dealings happened there and there was blood on the entire hotel staff's hands so they didn't dare utter a word of what they saw happen there.
That's why, when two men in suits showed up with a girl who was very obviously knocked unconscious, no one batted an eye. They were given a key to a room and not questioned whatsoever.
The security camera in the corner of the front office was all for looks anyway.