For the schools without supplementals, I would just prepare myself to answer the "what happened/why" question during the interview.
There isn't much else you can do, unfortunately, since the personal statement has already been sent with your primary application. =\
Don't freak out though! So, so many applicants have these blemishes in their grade reports, and your GPA and excellent DAT score are working in your favor. For instance, I took one semester of CC courses roughly 10 years ago when I wasn't yet ready for college and received a GPA of 2.10. Even though it was so long ago, I still gave full disclosure.
Not informing the schools brings about too much risk. Worst case scenario, this D+ holds you back this cycle, but you can work on something to boost your application over the next year for next cycle. On the other hand, if you don't inform the schools and they find out, this could take away all opportunity to apply in subsequent cycles.