On Line Grooming Hunter Sting Spirals Out of Control

A Hunter sting team confront an alleged on line child abuser in what should have been a routine sting. But things start to go badly wrong towards the end of the sting resulting in the target being left unattended and unsupervised and able to self harm..
What errors were made here, that allowed this situation to spiral out of control like this, and what lessons can be learned to make sure it doesn't happen again?.
This outcome, or outcomes similar, to any sting, attempted on an alleged on line child groomer, could result in legislation outlawing on line Hunter teams and sting operations all together.