I actually used Miracid, "Plant Food for acid-loving plants." Sorry about misstating that.

Was your lawn fertilizer a weed & feed product?

Stop fertilizing. They're growing too fast, thus the wood is soft, and the branches are splaying.

And as has been mentioned, was the lawn fert a weed-and-feed type? Also did any get into the shrub border?

Also, if you take the trunk by the hand, then move it back and forth while watching the ground at the base of the plant, does the ground move? (You should pull away the mulch for this "test.") If so, they're not yet rooted in.

So then you need to consider how they have been watered. By hand? sprinkler? soaker? or what?

And precisely where was the water applied?

If in the general direction of the shrub, it was likely shed by the foliage, thus never made it into the rootball.

And if by a sprinkler -- perhaps the lawn sprinkler(s) -- water probably never made it into the rootball.

Finally, physically check the soil in the rootball and surrounding it. Wet? Moist? Dry?

PS: Thanks for the pictures. It helps to see the shrubs, their condition, and placement.

When you added the other layer of landscape timber, did you fill it in? Maybe the roots are smothered.

Yes it was weed and feed