Is a free non-Muslim (Dhimmi) subject to qisas for killing a slave if the injurer later joins Dar al-Harb and is subsequently enslaved?

Primary text

If a free Dhimmi wounds a slave and subsequently flees to the Abode of War (Dar al-Harb), is captured, and then enslaved, he is not executed for the slave's death. The basis for this is that when the right to qisas arose (at the time of the injury), the injurer was free.