Pretty unusual. Most tractors/loaders do not have the strength of hydraulic force to break a loader like that. When they do break the ones I have seen usually break at welds and usually where some unusual leverage or bending was applied. I'm NOT a loader expert by any stretch but I've not seen this before.
I see where these FL series loaders are pre-stressed and the beams are narrower than traditional loaders. Claims are that they are stronger -- your buddy's experience brings that into question. I would think the MF regional rep needs to be contacted immediately and shown this break. And asked if there are others reported. Pretty serious stuff.