Although this did not answer my question you did give me something very helpful by mentioning I could do away with the decision step by using 'confirm end of processing'. I was able to eliminate alot of unnecessary steps in my workflow by doing this.
However, as I mentioned earlier, I cannot use attributes because Plant is not part of the key and I cannot add it as part of the key because the materials are created with and without plant assignment and the same workflow is used for both.