1) hmmm ambiguous but RAW would say that if within in 6″ its a surprise charge even if the move taking is 7-12″ as its “when the charge is declared” I’d play it as the move personally… but one for an FAQ /errata
2) its 1″ away from the wall of the building AND 1″ away from the vehicle so there would need to be a 3″ gap for them to move through
dont forget that limited number of pivots a vehicle can make & the heavy weapon bonuses for shooting said side… and once its destroyed it can be run over by the attacking infantry
