Did you also check the following two places:
1. Click the big round Office icon located in the top-left corner of Excel, then go to Excel Options...-> Add-ins-> Manage-> Dropdown to "Disabled Items"-> Go... do you find Digdb in the disabled items? If yes, enable it. That is what's causing the DigDB menu to be broken with only one command left
2. Go through the same Office-icon-> Excel Options...-> Add-ins-> Manage-> Dropdown to "Add-ins"-> Go... see if you can find "Digdb" in the list, if yes, check it; else, use the "Browse..." button to browse to C:\Program Files\DigDB\ to select DigDB, then ok out and make sure it's checked in the add-ins list. ok out.
Now you should have DigDB automatically loaded up in Excel 2007.