Interesting post. Looks to be plastic or other detritus from the flood, but could also be something unknown
i saw video of this right after the disaster. In it, the vapor appeared to zip through the house and exit out an attic or upstairs window on the righthand side. Which was not a straight path, but may have involved a stairwell, celing, or open "great room", not sure. It really looked like a form of materialization or dematerialization. Seemed to move with intention, but like you said it could just be debris. The thing is, if it was debris, I wonder how similar debris exited a second story window moments later. I think it moved along roofs after that, but visibility was lost. I havent yet relocated that video. I imagined it was someone with super technology like Star Trek, but of course, who knows.
In this video I don't yet understand why the purple posts are hazy.