I've had similar experiences a couple times while feeding F/T mice. They see it and strike at it but miss and then either lay on it or make half an attempt to constrict it.

I doubt the fact of the mouse being brown and in dim light had much of a factor. These guys are mostly active and hunt during the night.

I've found that most of the misses are due to the mouse being a lack of appropriate temperature (95-100 degrees). After all, BP's rely heavily on heat to sense the location of their prey.

It is kind of cute to see them look a little oblivious but you did did the right thing by making it warm again and offer it back!