I know Kit probably won't see this, but one of the reasons I think they're hanging up on him (if he makes it past them seeing VOIP) is that he's coming in REALLY hot. They can tell he's already fed up with them before they've even started the scam.
You can't blame Kit, I'm sure the same old song and dance gets boring after years, but the scammers are looking for pliable, obedient marks.
If you are very aggressive right off the bat (rather than a little while into the call, when they are sunk cost fallacied), they probably won't get anything from you anyways, so they just hang up.