Cody Kelly did that here on my local mountain same exact crack out both sides from the nipple. He continued to ride it all day like that........ expensive to replace for you I assume
Oi f*ck'os no moaning here as warranty will cover it. Rode it for another full day with no issues only took it off as it doesn't inspire confidence. Method employed to break it was to case a 25' double,square edge hit on stone. Hasn't gone right through. I have also bent my stem cause hero.