Hi Kristy,
Unfortunately not. It didn't appear that editing the message was possible. Especially in the digests. I believe I asked Customer Support too, and they confirmed it.
What I was able to do though was to edit the specific email notifications subject text.
It's still not a digest, but at least the notification emails are a little more descriptive than they were before.
I know that doesn't really help, but that's what we ended up doing.