One of my colleagues planted two Euonymous alata 'Compacta' at a client's home two years ago. We got a call from the client this week saying one of the shrubs was almost completely dead. Euonymous aren't my preferred shrub in light of their size but for the sake of symmetry the client would like a straight replacement. I am nervous to do a replacement though without knowing what killed the first one. The two shrubs are planted on either side of the front steps. They are against the front of the house on the East facing side in part shade conditions. They received adequate moisture and have no signs of distress from insects or disease. We are past the major heat of the summer and the client gave it extra water when the leaves began to brown believing it to be drying out. According to the client the decline happened quickly though she didn't give me an exact timeline. When broken, the branches do not show any signs of green on the inside. Does anyone have any suggestions as to why the plant would decline so suddenly?