FWIW, my local political group had some discussion about this and we actually did some digging. The Seattle people are not actually a formal BLM group or entity; they're part of a local group known as Outside Agitators 206. This
Seattle BLM FB page literally went live just yesterday; the two big names involved with the stunt are the ones running both groups' pages, though they're trying to deny a connection to each other.
Go ahead and call Mara Willaford to let her know how you feel!
https://twitter.com/alyssa011968/status/503272265077628928