split brass happens....
its either bad brass or bad barrel.
if this were my gun, i would check the barrel for any obvious signs of a defect.... altho it could be a wonky barrel that doesnt correctly support the case.
in my opinion, the more likely of the two is bad brass. i have seen new cases split in guns that have never had it happen before and after.... also seen surplus ammo split every 5 or 6 rounds.
hard to tell based on just one case, fired by another person.
i am sure the customer service guys will have you take it to a local gunsmith to have it checked out...
again, if it were me, based where the split is, i would be shooting instead of worrying (checking the spent brass of course)