Yea my bad, I recently converted from Stuct based data to class based data, so I kinda of glossed over the 2D array being struct based ><. There is a Set Members In <Struct> pin, that should be what you need to handle struct reference additions, but passing them around and keeping data parity is still another issue.
Something like this:
If I remember my previous setup, struct pins (direct lines in blueprints) are references, the issue comes when you enter and exit scope or set variables.