metal cam locks and dowels? you should be able to pull the lock down and
out once you have the arrow pointing to the outside edge

You still will not be able to shift the shelf if they are cam locks as the pins will still protrude into the shelf edge. If your lucky and can splay the wardrobe sides apart then you might get the shelf out. Otherwise without taking the wardrobe apart you will not take the shelf out or be able to reposition it the same way. A word of caution the fact the shelf is secured by cam locks suggests it is a structural feature as most shelves would only be supported by shelf bearers making them easy to reposition you may even find the wardrobe back is secured to the shelf.

A photo of the securing devices should confirm what are likely to be cam locks.

Richard