I know Botritus can cause that in Peonies and if it isn't that, perhaps it is another virus disease. Most fungicidal sprays cover a wide range of diseases but, to be sure you would have to take a cutting to the local county extension office for analysis.
An email to Esh or Eddie might get you a better answer.

I haven't figured out what to put on it...I am just not good with plants whenever a problem starts, LOL...but thank you for the advice. I will say that over the past week the leaves have gotten a little bit grey-ish. It is a shame. I have these HUGE bushes now, but not an ounce of color from them.

I will continue to persue a treatment.

If you cant figure it out you might call Goodness Grows ( it's their plant )They are always pretty helpfull.(706) 743-5055

I'm having this problem right now with several plants - none of them susceptible to botrytis as far as I know. What is causing it on my plants is a combination of the heat, the drought, and the watering restrictions. The constant drying out between watering is causing the buds to turn dark and dried out like the ones in your pictures. Could that be the problem?

I'm having the same problem...and I didn't notice it until this post. Mine is basically the only one in Atlanta that isn't blooming (except for yours). Let me know what you find out.