As cool as dom is the F&F plot has always been about Paul walker's character and his internal flight between duty and loyalty. In fast 4 the Feds killed any loyalty he had left when they arrested Dom. Now Brian has a family to protect. Dom's gonna get word about Letty so Europe sounds likely from the clip. Remember Han was supposed to be in Europe, so a good way to run into Letty or start competing ventures that brings Letty to light.