I know that it is late to chirp in here, but the case is this: Ventress must be alive to keep stacking offence. For example, if Ventress is dead and Talzin's lead means that Ventress comes back to life whenever a NS does a basic attack, and then Ventress dies again, and then, a few turns later, Daka rez's Ventress, then Ventress' offence is the same as it was when she died *the first time*. All of the rez's and deaths that she experienced do not stack her offence.
On the other hand, her offence stacks every time Zombie dies.
Try this for a fun squad (at least, it was fun before Jey... I haven't tried it since): GK, zBarriss, zzHermit Yoda, zVentress, Zombie. (GK and zBarriss are not necessary... Boba lead might be more fun. I have tried it with Boba lead and Scarif Rebel Pathfinder as well). Basically the idea is to ensure that Zombie keeps dieing, and Ventress is as hard to target and kill as possible.
Hermit Yoda puts Master's Training on Ventress and Zombie. Whenever Zombie dies, which is often, Hermit Yoda gets 100% turn meter and reset cooldowns. Also, Ventress gets powered up. So Yoda puts Master's Training on Zombie again. This calls Ventress to assist. You get a free assist from a continually powered-up Ventress each time that Zombie dies. You'll be doing 30k+ basics in no time. It is great fun.
(note: there is a bug with Hermit Yoda's "Do or Do Not". It doesn't actually work all of the time when Zombie dies. I submitted the bug report months ago, but no change yet)