Ministers decided to close the Hamilton School after inspectors, who arrived on February 7, 2014, referred three child protection cases to the police.
Inspectors also had to intervene in two lessons after “serious health and safety risks were observed” at the top fee-paying school.
The nursery study said staff failed to keep accurate information on children’s “life-threatening allergies”.
Inspectors discovered children as young as 12 months were also expected to feed themselves without staff support – even when unable to do so.
Education Secretary Mike Russell labelled the report which led to the closure the “worst” he had ever read.
A Care Inspectorate spokesman said it had “extremely serious concerns” about the quality of care offered to young children.
The city council spent more than £250,000 providing places for 98 children to be educated for five months after the fee-paying families were left without childcare.
In February 2014 children initially entered Braeside Primary, which was hastily reopened after being mothballed. By July, only 47 remained, and by the beginning of the new term all pupils had found an alternative school.
Following the closure, school owner and principal Kathlyn Taylor and her employee Hannah Jamieson were charged with alleged offences against children.
But in January 2015, the Crown Office has confirmed nobody will face any criminal charges over allegations stemming from the school.
The fee-paying school was considered one of the best in the city.
