He was due to appear in court again on October 11.
Kennedy, who has served hundreds of youngsters in almost 30 years of the Children, Young Person and Their Families Act, said "he's where he should have been in the first place".
He said he and others are "pulling our hair out" over the failures of the system in coming to grips with issues involving young offenders.
He said the act says "they" have "got to find them a bed", and on the wider issues "if they haven't got it sorted out they're not going to now."
"It's pretty simple ... it shouldn't happen," he said. "There should be a bed somewhere."
The boy had been placed on bail in the care of Oranga Tamariki, with a 24-hour curfew, when he first appeared on a robbery charge on September 6.
In the Youth Court last week, when the boy was charged with breaching the conditions of bail, Judge Peter Callinicos was told that the motel minder would not have the ability to restrain the juvenile, who would be thus able to leave as he pleased.
"If this arrangement is a policy of Oranga Tamariki then it is an extremely serious situation, one which is going to lead to a tragedy," Judge Callinicos said, after being told the boy had absconded three times.
It was "almost in the realms of the bizarre", he added.
Wellington, East Coast and South Island regional manager for Oranga Tamariki, Peter Whitcombe, said children in some situations might have to wait until the next day before a room became available.
Minister for Children Tracey Martin said Oranga Tamariki "has to deal with some really challenging young people", and law which makes it clear children aged 12 and under should be kept out of custody if possible.
"However, they walk a tightrope and sometimes things will go wrong," she said.