Does the encryption process not start or does the preboot authentication not start? DEGO I believe just takes a look at basic computer information and makes sure you don't have a bad HDD. Which version of Drive Encryption are you installing? Are the computers having issues different models or brands?
You can force McAfee to do an update and talk to the ePO server. As far as I know that's the only way to try and get the Windows credentials to sync faster.
You should be able to update through a product update task, but before doing such things I would contact support. Encryption updates are a terrifying beast.