My quess is the ‘’object’’ was ice from a plane. There are a few private airports out that way, could have fallen from a small plane. What you may have seen at sunset was the reflection of a satellite,seriously. There are loads of them orbiting Earth and they sometimes catch the Suns reflection. What season of the year was this when you saw this? Just curious.
All satellites reflect sunlight, when not inside the earths shadow. Without the sunlight, we would not be able to see any satellites. Any reflection from sunlight off a satellite at sunset would be extremely small, pin point or star point like, and mostly washed from the light of the sunset.
I would think confusing a satellite with a UFO would be unlikely. In addition, the observer stated the object did not seem to fly in a straight line. Satellites orbit in what appears to be relatively straight lines, and can appear as aircraft to those not familiar with satellites.
I have never observed a satellite making turns or not moving in what appears to be a relatively straight line.