If I was playing any other Clan, I wouldn't have a problem with your plan. But the Giovanni are first and foremost devoted to the family. Basically, they are loyal to nothing else. They are one of the few Clans (if not the only one) that have no antitribus, no dissidents, no defectors. There's no way I'm going to roleplay betraying an Elder or allowing you to betray him simply because that would weaken the Clan's position in the big picture.
And, at any rate, do you really think a handful of fledgelings can take on an Elder and his retainers, in his own lair? Are you out of your minds?