Off the top of my head, I don't think you can. You would need to datalinq those scene group children scenes I think to pull the data from something like a text file (or use layout mode)
One other approach you might want to experiment with instead of using a scene group, is to use a Sequencer Group. Create a sequencer group in the sequencer and drag a few scenes in it, then you can set the sequence group to "Roll" mode. It will roll all of the sequencer take items you've put in that sequence group. You can still adjust the properties of the roll, such as the margins between each page etc, using the properties of the sequencer group. This method will definitely allow you to use the template data to edit the text of the credits, and it is very easy to add/subtract pages from the roll, simply by adding or deleting the take items from that sequence group. Hope this helps and makes sense..
#XPression