When I use secure, I never mean that there's zero chance of a freezing. That's impossible.
The term means that, relative to being unsecured, precautions have been taken to lesson the chance of TNT thinking you're sketchy.
If I cracked an inactive and give you the password, you could get frozen.
But if I cracked an account months ago and give you the ip, original email, all three passwords used by the account, and the pin and birthday? Hell, even if the original owner filed a ticket, you seem more like them than they do!
The point is, there is no 'completely secured" or risk free account. Sellers denote accounts as 'secured' to show the added security. I sell accounts for which I don't have all this information. And for those accounts, you have less of a chance to get away with cheating. But for the most part, inactive is inactive, and as long as you aren't being a dumbass, it should be okay.