Naders close up pic is of Octalink V2, the longer splines give it away.
I compiled all the knowledge I could find regarding these cranks in a single thread here:viewtopic.php?f=1&t=252065
To me it appears that your cranks have been ridden without having been fully engaged on the splines (more torque is required than expected on the BB bolts) or an attempt has been made to mount to an Octalink V2 BB. The spline width (not length) between V1 & V2 is very slightly different, 2mm Vs 2.2mm IIRC.
I think your cranks will be ok once mounted to a V1 BB, but I'd mount fully, remove, clean out the broken off burrs, and remount.
For your cranks, it is very important to remove the extractor rings from the cranks before fitting the cranks to the BB so you have full feel of spline engagement.