Conquerors’ Pride by Timothy Zahn (Conquerors 1)

The meeting wasn’t planned. When the humans started their first-contact protocols the alien ships opened fire without warning. The fight was brutally efficient, the aliens even killed the escape pods. Pheylan Cavanagh disabled his emergency beacon before the aliens could target his pod but the pod is taken away inside one of the alliens ships instead before they leave for parts unknown.

Lord Stewart Cavanagh, Pheylands father is denied an official mission to rescue his son so he finances his own. Adam Quinn leads the rescue team. We are also introduced to the different races and conflicts in the human dominated alliance.

The alien point of view is an added spice. Their life after death biology is unique in science fiction.