"In my opinion they volunteered because their boss asked them to."
Translation:לפי דעתי הן התנדבו בגלל שהבוס שלהן ביקש מהן.
It should be: "לפי דעתי הן התנדבו כי הבוס שלהן ביקש מהן", And not "שלהם", because we are talking about females.
Can't see anything indicating that we're talking about females. The entire sentence is masculine.
Wrong, it's accepted. We also accept מכיוון ש and other alternatives. It will possibly be removed in the next version anyway.