*this assumes both a successful scum-lynch the proceeding DP, but also assumes a doc save in cojunction. Once ur at MYLO ur stuck there at best unless you lynch scum AND get a doc save..
VTNL'ing itself does not cause that extra night, nor does it provide town with an additional mislynch in itself. Nor does it provide town any better probabilities than already present in a 1/2(50%) "CC".
This is why in classic set-up you VTNL. Because you can guarantee it's a true CC in whuch there is only one cop. And you can guarantee there is a doctor in the game that has 1/4 odds of protecting the NK target.
Neither of those two can be guaranteed here. Nor, again, does no-killing or VTNL'ing itself cause an extra mislynch. The risks are there, but they're minimal in closed set-ups.
Just like there is a minimal risk we're both town, and VTNL'ing presents the opportunity for scum to kill one of us, leading to the lynch of the other and a town loss. If the above is scummy because I disregarded such risks as minimal, then you are doubly scummy for disregarding the risk of both of us being cop. Especially since, unlike the risks of no-killing which require a doc save in conjunction with a successful lynch for those risks to come to fruition.
The only thing that need be true here is we are both cops. Nothing else need happen in conjunction for that to backfire. So arguably the risks is less minimal than the risks of no-killing, although arguing still in the "minimal" range.