Excavation 101

So this tutorial at least when I completed it was fairly useless because of the number of people around and how the phasing with everything was working. But the process for the digs are:

Speak to Roska, this will place a marker inside the quest area that has a small column of smoke/dust "Disturbed Earth".
Go there and use your totem (it'll be on your quest list or in your inventory) to place your totem and then click on it in the open world to empower the elemental.
Now there will be three things you can interact with: 1) The Totem and 2) some competing elemental objects in the world. These two will move the elemental balance bar.
3 is a pile of rubble with a 0-100% gauge above it, you need to click on this whenever the elemental balance is in range in order to dig.

In general, once you get to the actual dig, click your totem to start the elemental bar moving to one end and click the rubble once it's available. Your character will continue to dig away as long as they can so you don't need to click multiple times. If you're lucky you won't have to bother interacting with anything else or balancing the bar. Completing it with other people around still seems like it can cause issues so sometimes you may have to fly away or even abandon and retake the quest to continue.

Sometimes when empowering your elemental a mob will spawn rather than a dig site starting, just kill it and move to the next spot you can find in the quest area.
You can also occasionally find "Just a Rock" which will eventually get you an achievement for finding 10 of them.

I didn't even get this quest, I only got The Big Dig.

No, the whole quest is just broken. It tells you to balance the bar with water, but you only have fire so you can't excavate the third find. Everyone here has given up already.