There are various news stories relating to this event. one child was in a protracted coma from hypoxic brain injury.
The number of SN fatalities from a medical perspective is quite low with most being within the last decade. Very few people survive a dose over 10-20g with almost all of these due to medical intervention. Of this very, very small number, most don't have lingering effects.
That said, there have been many more CO deaths, and the basic mechanism of injury is the same in both (interfere with the RBC's ability to transport oxygen). There absolutely can be and are cases of lingering neurologic complications from CO poisoning, even if the majority of those who recover from CO poisoning have no ill effects.