Many years ago friend's S15 pickup with V6 broke the crank in half.
Another friend started it up, drove it on the trailer knocking to beat heck. (I was not there)
Anyhow reman .010/.010 crank new bearings, flipped the engine upside down on the engine stand completely assembled.
Swapped out the crank and bearings. In 24 hours he was back on the road again, ready for work Monday morning.
He drove it many years after that.
Had never seen that before, where the crank snaps in half, but in a manner that it still turned the front half of the crank.
Kind of what the OP has pictured above.
Glad you caught it early before it grenaded the whole engine.
☆☆☆☆☆