The NTSB have confirmed the PAPIs for 28L were operational at the time of the crash. They were subsequently damaged and hence NOTAM'd as inop which may have caused some confusion as to their status.
I am a little surprised that after such a catastrophic accident and a large charred airframe sitting at the side of the runway, that someone filed a NOTAM that the PAPI are OTS. After all they are for a runway that is going to stay closed for a significant period of time.
Presumably there was other infrastructure damage (GP antenna, met sensors, runway edge lights to say the least) but these are not NOTAM'd.
The only reason I can think of is that the PAPI form part of the overall visual picture that crews might expect to see when visually acquiring the airport?