But, which kind of bribe are we talking about? How could it work out in practice for an AI to acquire something valuable, and at the same time prevent it's human operators from taking it without its consent?
There's so many angles to go at it too, beyond bribery and threats - humans can be tricked, nerd-sniped / baited by exploiting their curiosity or worries, overwhelmed with information or raw sensory input, etc. Depending on whether there's more than one operator involved, the trick may involve playing one human against another, etc.
Hell, humans get tired; I wouldn't be surprised if an effective breakout happened just because agent output something that, at first glance, looked like system-level message that makes the operator do the wrong thing in panic, or from muscle memory. Simple thing like:
$ sudo journalctl ...
password: