Anyone in management who can tell me if this is U?

[FizzyCherry]

I have mentioned this already on another thread but could someone more qualified than me please advise.

I work in an industry with vulnerable people. If we have any suspicions about any of our charges, we are duty bound to report it in strictest confidence, or so I thought. It's then looked into and a case file created if necessary.
Yesterday, a colleague had cause to report an allegation about another colleague, that probably is quite likely untrue, but as we were working together we agreed between us better to be safe than sorry and we couldn't not report it. AFAIK it's the only such allegation made, person making allegation is very new to us, so there's very little opportunity for a past to have developed, if that makes sense?
Accused colleague has now been approached by management directly and told of the allegations, and by power of deduction, who has accused them.
From what's been said, it seems this person has seen the written report which is handed to management in confidence.
This person has angrily approached my colleague today about it - I was off today, but no doubt will get my turn on Monday.
I am absolutely gobsmacked by the way it's been dealt with but don't know what to do about it.
I was under the impression in this situation that more evidence might be gained or that a situation might be monitored further - it wasn't something that I thought required immediate action, just something that if, repeated, might be a problem.
From what we can gather, management have gone straight to the person within a couple of hours and said "Fizzy and her friend say you did this."
I think I am set with what I will say to the accused person if approached, that I am trained to report ANY concern, even if I doubt it's true, but what do I do about the situation with management?
Should it have been dealt with in this way?
There is a level of management above the manager in question but I don't feel confident in taking that route, plus to do so I would have to breach the original confidentiality.
It's affected my confidence in reporting other concerns in the future, although I know I must, but I'm worried about the repercussions.
AIBU to think this was inappropriate? I'm debating leaving a job I otherwise love because it's so important that we can trust our management with things like this and I don't think I can any more.
Or am I overreacting?

In organisations where everyone understands how the procedure works, the fact of having an accusation reported will not harm the accused at all unless it is substantiated - everyone knows that it is an occupational hazard, and also knows that no-one has any alternative but to report.

I work in the sector you are referring to as a manager and I have dealt with several investigations involving members of my and other managers teams. It's the nature of the sector we work in. I've had to report team members due to concerns and have had allegations of abuse raised against me by clients. The most important thing is to work within the adult protection legislative framework and remember your clients safety and wellbeing is paramount. Your manager has dealt with this badly, where possible any such allegation should be looked at by an independent manager

So the accused reacting in this way is really ill-advised - if they had not done what they were originally accused of, there would have been no repercussions. However, threatening colleagues is definitely something that can leave a blot on your copybook at work!