I had the same problem on a Genesis Gold. Did similarly except I was fortunate to have a friend who at the time owned a sheet metal shop. He welded in a stainless steel replacement.
I wish I had that still available to me, but you can buy stainless frame tubing and do exactly what Bruce did by attaching using the inserts with 1/4" bolt openings. The stainless may be overkill, but as Bruce said, this is probably the most failure-prone area on the frame of a Genesis.