Now, just thinking out loud, if it's just the last row of data, you could do a couple of things, again still, both a bit clunky.
Create a second datagrid instance with it's only datasource being the last row you want and add it to the scrollView (https://www.shinobicontrols.com/forum/shinobicontrols/2013/5/add-a-quotadd-newquot-button-below-the-grid). Then reposition the grid on scrollViewDidScroll.
Create a new datagridrow instance and loop through the cells, set the data for the cells and then change the new cells' coordinate property to the corresponding cell's coordinate property in the last visible row.
I know #1 will work but #2, in theory, it sounds like it could work but I've never tried it.