You are basically choso death painting womb. Kenjaku with his mind swapping technique killed summer rose and gave birth to Ruby.

Kenjaku is not loyal to Salem more like business partners. So creating the death paintings and the Ruby was because he wanted to.

BUT Salem needed Kenjaku to cause Mass panic. So he is responsible for what happened during the falling of beacon.

A few weeks prior Team Rwby stumbled upon Eso and Kechizu your younger brothers. They did not survive against Rwby