I think many "building codes" are Nanny-state B.S. and I'd like to repeal most of them.
That being said, I don't know what I'm looking at in this pic. Is that a hot big black line, or a ground?
If it's a dedicated ground line, and somebody needed to attach another ground line from some other circuit to it, what's wrong with (1) cutting away the insulation, and (2) wrapping the #12 wire all around it, copper-on-copper with a lot of contact, and then (3) securing the connection with hose clamps?
It looks like a solid ground to me, assuming the other end of that big wire is properly grounded into the dirt.