While withdrawing the submissions in question (which has taken place as of this post) is the right thing to do, and I at least appreciate your apology and hope the other members of our community will accept it as well, I'm going to close this thread and leave everyone with two reminders:
1) It is indeed against our community rules to submit others' User Content without their express permission. Doing so repeatedly can imperil one's ability to participate in User Content.
2) It's also against our community rules to use UC comments or forum posts to "call out" people who have "borrowed without permission." The proper response is to either PM the 2D Steering Committee (Emwsand, Sadet, Toshiro, and myself) or file a
support request.
That said, I hope everyone involved can live and learn from this experience so it doesn't get repeated again.