Complex sentence: The group is forced to call upon their Uncle Gamlen Amell, who no longer holds the fortune and estate held by the Amell family, forcing Hawke to enter the service of either a mercenary band or a smuggler group.
Split into simpler sentences: The group is forced to call upon their Uncle Gamlen Amell, who no longer holds the fortune and estate that used to be held by the Amell family. Therefore, Hawke sees no choice but to enter the service of either a mercenary band or a smuggler group.