This is merely a guess on my part. But since Interop works, whereas Law Dispatch does not, that may because the "paste" process from Excel is triggering the Service Type based on only the first letter. There is only one type that starts with the letter I. But there are three that start with the letter L (Law Dispatch, Law Tac, & Law Talk). Remember that if you need to flip a group of entries for service type, alert color, or some other setting, you can do that in the Favorites Editor.
Go to the first item in the group (department) that you want to change. Click on it, and make your setting (type, color, whatever). Once you've done that, and hit OK. That item will still show as selected.
Hit <CTRL> + <C> to copy that to the clipboard (or use Copy from the menu after a right-click).
Now, hold down the Shift key and click on the last item to change. That will select the column, You'll get a pop-up to edit the last item, but hit cancel.
Now, with your list of items selected, hit <CTRL> + <V> to paste the color or type, or other item, to all of the seolected items.