Not really, "A vehicle with a wercking ball causes a str9 hit upon one unengaged enemy unit within 2" at the beginning of the assault phase
on a roll of a 4+"
Is different from "At the start of each assault phase a vehicle with a wrecking ball rolls to hit against on unengaged enemy unit within 2", on a 4+ that unit suffers a str9 hit." The vehicle doesn't actually make any attacks, there's a set of conditions (<=2", & <12"

and a result, there's no assault, which is needed to make close combat attacks unless the wargear states itself 'counts as a close combat attack'. A 'hit' is a generic term where as a "Roll to Hit" is actually a part of the shooting process it's own specific term where "To determine if the firing models have hit their target roll a
D6 for each shot that is in range" Page 17 most importantly 'to Hit' rolls rely on
BS to determine the result.
It would be like saying anything that happens on a roll of 3,4,5,6+ is an attack because the conditions have been satisfied, which would include which would include things like shock prows and grot riggers and they wouldn't be able to be used when shaken or stunned because they would have a 'Roll to Hit' thus be an attack/weapon of some kind by your reasoning.