I was thinking the same thing since it is only bittering it shoudnt add any flavors or aroma.
EDIT: I bought all the ingredients except I got irish ale liquid yeast. I plan on brewing this tonight when the kids go to sleep so it will be another long night. 2.5 gallon Batch
EDIT I brewed this yesterday for National Home Brew day and everything went great. I also ordered a 6.5g minibrew conical fermenter. Now all I need is a stir plate and a 8 gallon stock pot and I should be able to do 5g all grain.
You could try giving the fermenter a swirl to suspend some yeast so they can have another go at it. There is tons of yeast in there already, I wouldn't bother adding more. Raising the temperature a few degrees can also wake up the yeast.