Yes, noticed this too and it's been nagging at me. The timing was way too precise to be coincidental - the TFR went up roughly 40 minutes before the first reported sightings, which suggests whoever filed it knew something was coming.
Dugway's had quiet periods before but this one felt different. There's a small group over on another forum that's been cross-referencing the NOTAM data with ADS-B exchange logs from that night and some of the gaps in the transponder records are genuinely strange.
What I keep coming back to is that TFRs for Dugway aren't unusual on their own, its the radius on this one that stands out. Much larger than the standard restricted area. Anyone else pull the actual coordinates and compare them to where the light reports were clustered? Would be worth mapping that properly if someone has the time.