Is grounding the gas meter required?

[LarryFine]

It is unlikely a grounding electrode connection would have changed much. Nothing in the house is designed for MV so it is just going to find the path of least resistance for most of the current and the wires just are not going to be big enough to trip the protection relays on the MV side fast enough to do any good.

I believe a 10' #4 cu would have carried much more of the fault current than the 25' #10 cu had to.

Note: This was in an older home with all-copper plumbing and metallic water distribution lines.