A child may be held in a juvenile detention facility if the intake worker determines that one of the following conditions applies:
(3) The child consents in writing to being held in order to protect him or her from an imminent physical threat from another and such secure custody is ordered by the judge in a protective order.
(4) Probable cause exists to believe that the child, having been placed in nonsecure custody by an intake worker under s. 48.207 (1) or by the judge or a circuit court commissioner under s. 48.21 (4), has run away or committed a delinquent act and no other suitable alternative exists.