As per the Entagled rule on page 68 of the big rule book States
"Being involved in a vehicle crash due to weapons fire is extramely unpleasant......" So and assult wont entagle a destroyed 
vehicles passengers??  Wrong!

How about this line from page 38 under who can fight .

Close combat is a swirling melee of troops leaping spinning,hacking and slashing one and other. As well as fighting 
hand-to-hand, warriors will be firing and point blank range at any target that presents itself "

And from page 71 under Infantry Assulting Vehicles 

Infantry can pose a greave risk to vehicles if they get close enough. With the right weapons, troopers can wreck a vehicle 
by shooting through vision slits, planting explosive charges on fule tanks, 
tearing open hatches to attack crew members or committing some other equally imaginative act of mayhem.

So... assults can include close range weapons fire, so if a vehicle is destroyed by an assult it can be due to close range 
weapons fire as part of the assult, and so they are entangled.