If we need to re-assign stereo parities to the bond-broken structure, I see two approaches:
Pass in a parity evaluator that simply returns True no matter what, which will assign arbitrary parities to all unassigned stereocenters that appear upon bond breaking.
Calculate stereo from a geometry, if you have one, or generate a geometry and calculate stereo based on it.
If we need to re-assign stereo parities to the bond-broken structure, I see two approaches: