The 4th edition of the "Fruit, Berry and Nut Inventory" book says that the Anna and Golden Dorset are Southern apples, warmer winter apples. I am thinking you must be in such an area. 

I wonder what your soil is like. If you have a heavy clay soil and returned a highly amended mix to the planting hole, and are 'fertilizing' heavily, it's  possible that you've got an environment that is essentially a pot within the ground. The roots can't/don't need to to reach out of the root ball zone in search of water and nourishment, and so create more and more mass within that area, essentially becoming root bound. That could stunt the tree.

The common wisdom, around here is, to layer mulch organic material primarily, and some compost if you feel the need, to the soil surface, rather than fertilizing specifically. Oh, and jab through the shovel glaze of the original planting excavation. If that all sounds plausible you can probably, with care, dig her out and fix the hole and unwind the roots and replant the three year old. Maybe not while its really hot and dry. but put it in the plan. 

If I'm barking up the wrong tree, you might try a little pruning to encourage some scaffold/side growth and strengthen those competing leaders.  

The pictures are not focused on the details of fruiting, from what I think I see, they look a bit like tip bearers. Do you notice that habit ? Or partial spur bearing?   That info is not in the FNaBI book for these varieties.   When required by growth,  your pruning approach will vary a bit if you have any tip bearers.   Spur bearers, here anyway, are the far more common fruiting habit.

And do you know what Root Stock they are grafted on? 

It looks like you've tipped the Fuji. If you saw green cambium it is still viable, if not, cut back to just above a bud a little further down stem, until you see live cambium.   If you are pruning back the other more dominants, you may get a little more juice to her as well.

Hope this helps.

I'd still look into pruning a little; to strengthen and encourage lateral growth off those two leads, and I think it would lend some energy to the fuji. As long as it has some green cambium still. Consider it a little early fruit thinning.