Fuzzy light moving across sky in twilight

While attending an evening ranger program in the amphitheater at Phantom Ranch (in the bottom of the Grand Canyon), a few people looked up and saw a strange, fuzzy, foggy white light moving roughly west to east across the sky. The sun had just gone down and a few of the brightest stars were starting to appear in the twilight. The UFO light looked like it was shining through a cloud--though the sky was completely clear; stars appeared crisp and clear. Additionally, the object was silent.
I'm aware there was a SpaceX launch this evening; however, I've seen SpaceX rockets in the sky before and they do not move this quickly and they usually leave a trail. I've seen countless satellites, the ISS on multiple occasions, and other phenomena, but this one seemed different. The light intensity on this object stayed the same during its path across the sky. And it was not dark enough to see satellites yet.
My background: I'm a park ranger, trained in astronomy, with many hours of stargazing experience. I was on an overnight hike during a work trip to Grand Canyon with several ranger colleagues who also saw the object. We were in the amphitheater audience at another ranger's evening program. Other members of the public who were in attendance saw the object as well.
Our latitude & longitude: 36.104642, -112.095122
From our vantage point looking south, the object was flying roughly ESE, almost but not directly overhead.
Falcon 9
Starlink-101 (6-11)
SpaceX
SLC-40, Cape Canaveral SFS