So it looks like I'm wrong in my post above... but I don't know what the issue is. I say that because after a new row is created, and I click in the ChartOfAccountNumber column, I see both the RadTextBox and the ImageButton defined in that template. So that's good. However, the javascript that referenced those controls was no longer working. But after some more digging, I found that in my OnBatchEditCellValueChanged function, I was getting the row index via args.get_row().sectionRowIndex, which worked before, but didn't for the new rows. Once I changed that to get_masterTableView().get_selectedItems()[0] it starting working again.
Is that expected behavior?
Also, the checkbox is giving me problems, and is displayed as blank. And if I try to change it by checking it, it puts the word "true" in rather than a checkbox. Why is that? And how can I initialize all the columns in the new rows to certain values?