Skipping around Personal Story

So, I'm running a lvl 80 Guardian Dragonhunter and I'm at the Mouth of Zhaiton (I almost wrote "Mouth of Sauron") event. From previous experience, I think this event is a pain in the backside and I'd like to skip it if I could and maybe come back to it later. Is that possible? Or do these things HAVE to be done in order?

there is a mouth of zhaitain in kitah manse, and a mouth of zhaitain in arah (victory or death).

for the first time you deal with the mouth, after revealing the secrets of the eye i always choose to stop the supply ship instead of a direct attack- the direct attack leads to fighting the mouth under kitah manse and he has the knockback adds that must be sniped from range (pick up rocks around the area if no weapon) before you can hurt him. While the supply ship is, i'm pretty sure, longer, the mouth fight itself is mainly a matter of watching for confusion on you, and that's about it.

neither of these can be skipped - and i will say, for victory of death in particular, not meeting one of the story objectives tends to break the instance and not award completion after zhaitan dies. even if there was some way to skip it, i doubt the instance would work, but AFAIK there is no way to avoid it.

Yeah, now I wish I had chosen to hit the supply ship.

The personal story must be done in order, there is no way to skip one step and come back to it later. However the personal story as a whole can be skipped, either to do another storyline (on a level 80 character) or to focus on other activities. If you want to switch to a different storyline you'll need to open the hero panel, click on the story journal (star icon on the left side) and pick the one you want to play, then there will be a button in the window to start it. And if you want to do non-story content you can just go ahead and do it.

Each expansion or living world storyline is separate and can be played in any order, but like the personal story you have to go through an expansion or episode in order the first time. So for example you can start playing PoF as soon as you reach level 80 without completing the personal story, HoT or any of the living world, but you can't skip the start of PoF and go straight to the final fight or something in the middle. Likewise you can skip a whole living world episode, but not a single instance within one.

After you've completed it the first time that character will get the option to reply a specific instance (so you can attempt the achievements without having to do the entire story again) but other characters on your account will have to start from the begining.