I’d say it looks like you don’t have much choice now but to use the two 8-foot ground rods anyway. It’s too bad, since all the concrete guy really needed to do was roll out a lousy 20-feet of #4 Cu in the footing before he poured it and just leave a tail for you to connect to and everything would have been fine. Instead the building owner is stuck with the crappy rods and some #6 Cu for a grounding electrode.
