Ouch. Makes me cringe. Good luck getting it fixed. A couple things I notice. I think this is beyond a weld repair. Can it be done? Most likely. Will it hold, depends on loading. Will you ever feel comfortable with running it at load? I would always be worried when I'd hit something with a shank or a mower that would stress the welded area and cause it to break. I'll also say that this does not look like a great casting to me. I see some thin wall sections like around the right side middle area. The way the bolt hole flange cracked and broke is crazy. And it looks like there was a crack along the lower surface that shows fatigue before fracture. Amazing what the new cameras can reveal with just a photo. If the dealer added the hoe for you, I'd certainly lean hard on them for free labor if not entire repair costs. If they didn't add the hoe, I would still try to ask the manufacturer to assist. However, that could be a long drawn out process. They are notoriously slow in response to these sorts of things and would likely attempt justify "no fault" due to the hoe. But worth a shot IMHO. Sometimes too the dealer will show mercy and make you pay for parts while they "absorb" the labor on a warranty claim.
It seems that the grain size on that casing is fairly large too......out of spec...doubtful. But for cast steel/iron in todays world, seems fairly granular. Assuming it's not Aluminum as I see some corrosion.